Question: When did the relationship between the artist having with the most UK hits in the 80s and Carlos Leon ended?

full_context: Document 1: List of UK Singles Chart number ones of the 1980s: American entertainer Madonna was the most successful act of the decade in terms of number - one singles. She had six number ones: ``Into the Groove ''(1985);`` Papa Do n't Preach'', ``True Blue ''(both 1986);`` La Isla Bonita'', ``Who's That Girl ''(both 1987); and`` Like a Prayer'' (1989). George Michael had significant involvement with seven number - one singles; he was also involved with Band Aid single ``Do They Know It's Christmas? ''but his contribution was less significant. He had two number - one singles as a solo artist, four as a member of pop duo Wham!, and one as a duet with Aretha Franklin. The following artists achieved three or more number - one hits during the 1980s.
Document 2: Madonna (entertainer): Madonna's popularity was further enhanced by her film roles, including Desperately Seeking Susan (1985), Dick Tracy (1990), and Evita (1996); the latter earned her a Golden Globe Award for Best Actress. However, most of her other films have been panned by critics. Her other ventures include fashion design, writing children's books, and filmmaking. She has been acclaimed as a businesswoman, particularly after she founded entertainment company Maverick (including the label Maverick Records). In 2007 she signed an unprecedented US $120 million 360 deal with Live Nation.
Document 3: Madonna (entertainer): After its release, Evita garnered critical appreciation. Zach Conner from Time magazine commented, "It's a relief to say that Evita is pretty damn fine, well cast and handsomely visualized. Madonna once again confounds our expectations. She plays Evita with a poignant weariness and has more than just a bit of star quality. Love or hate Madonna-Eva, she is a magnet for all eyes." Madonna won a Golden Globe Award for Best Actress in Motion Picture Musical or Comedy for the role. She released three singles from the Evita soundtrack album, including "You Must Love Me" (which won an Academy Award for Best Original Song in 1997) and "Don't Cry for Me Argentina". Madonna was later presented with the Artist Achievement Award by Tony Bennett at the 1996 Billboard Music Awards. On October 14, 1996, Madonna gave birth to Lourdes Maria Ciccone Leon, her daughter with Leon. Biographer Mary Cross writes that although Madonna was often ill during the filming and worried that her pregnancy would harm the film, she reached some important personal goals: "Now 38 years old, Madonna had at last triumphed on screen and achieved her dream of having a child, both in the same year. She had reached another turning point in her career, reinventing herself and her image with the public." Her relationship with Carlos Leon ended in May 1997; she declared that they were "better off as best friends." After Lourdes' birth, Madonna became involved in Eastern mysticism and Kabbalah. She was introduced to Jewish mysticism by actress Sandra Bernhard in 1997.
Document 4: Madonna (entertainer): Besides singing Madonna has the ability to play several musical instruments. She learned to play drum and guitar from her then-boyfriend Dan Gilroy in the late 1970s before joining the Breakfast Club line-up as the drummer. This helped her to form the band Emmy, where she performed as the guitarist and lead vocalist. Madonna later played guitar on her demo recordings. On the liner notes of Pre-Madonna, Stephen Bray wrote: "I've always thought she passed up a brilliant career as a rhythm guitarist." After her career breakthrough, Madonna focused mainly in singing but was also credited for playing cowbell on Madonna (1983) and synthesizer on Like a Prayer (1989). In 1999, Madonna had studied for three months to play the violin for the role as a violin teacher in the film Music of the Heart, before eventually leaving the project. After two decades, Madonna decided to perform with guitar again during the promotion of Music (2000). She took further lessons from guitarist Monte Pittman to improve her guitar skill. Since then Madonna has played guitar on every tour, as well as her studio albums. At the 2002 Orville H. Gibson Guitar Awards, she received nomination for Les Paul Horizon Award, which honors the most promising up-and-coming guitarist.
Document 5: List of artists by number of UK Singles Chart number ones: In addition to his number ones as a member of The Beatles, Paul McCartney has received an individual credit on three more (``Ebony and Ivory '',`` Pipes of Peace'' and ``Ferry Cross the Mersey ''charity record) and as a member of Wings (`` Mull of Kintyre'') as well as four more charity records (``Do They Know It's Christmas? ''by Band Aid and Band Aid 20,`` Let It Be'' by Ferry Aid and ``He Ai n't Heavy, He's My Brother ''by Justice Collective), making a total of 99 weeks at number one with 25 different singles, including the biggest selling single of the 1960s, 70s and 80s (`` She Loves You'', ``Mull of Kintyre ''and`` Do They Know It's Christmas?'').
Document 6: George Michael: George Michael (born Georgios Kyriacos Panayiotou; 25 June 1963 – 25 December 2016) was an English singer, songwriter, record producer, and philanthropist who rose to fame as a member of the music duo Wham! and later embarked on a solo career. Michael has sold over 115 million records worldwide making him one of the best-selling music artists of all time. He achieved seven number one songs on the UK Singles Chart and eight number one songs on the US Billboard Hot 100. He was widely known for his success in the 1980s and 1990s, including Wham! singles such as "Wake Me Up Before You Go-Go" and "Last Christmas" and solo singles such as "Careless Whisper" and "Faith".
Document 7: Second British Invasion: During the Second British Invasion, established British acts such as Queen, David Bowie, Paul McCartney, Phil Collins, Rod Stewart and Elton John saw their popularity increase; a few acts that dated to the era of the original British Invasion, including George Harrison, Eddy Grant, The Hollies and The Moody Blues, had their last major hits in this time frame. Counting his work with Genesis, Collins had more top 40 hits on the Billboard Hot 100 chart during the 1980s than any other artist.
Document 8: Madonna (entertainer): Madonna is dedicated to Kabbalah, and in 2004 she adopted the name Esther which in Persian means "star". She has donated millions of dollars to New York and London schools teaching the subject. She faced opposition from rabbis who felt Madonna's adoption of the Kabbalah was sacrilegious and a case of celebrity dilettantism. Madonna defended her studies, saying: "It would be less controversial if I joined the Nazi Party", and that her involvement with the Kabbalah is "not hurting anybody". The influence of the Kabbalah was subsequently observed in Madonna's music, especially albums like Ray of Light and Music. During the Re-Invention World Tour, at one point in the show, Madonna and her dancers wore T-shirts that read "Kabbalists Do It Better". Her 2012 MDNA album has also drawn many influences from her Catholic upbringing, and since 2011 she has been attending meetings and services at an Opus Dei center, a Catholic institution that encourages spirituality through every day life.
Document 9: List of Billboard Hot 100 chart achievements and milestones: Number of singles Artist Biggest number - one † 20 The Beatles ``Hey Jude ''18 Elvis Presley ‡`` Do n't Be Cruel'' / ``Hound Dog ''Mariah Carey`` We Belong Together'' 14 Rihanna ``We Found Love ''13 Michael Jackson`` Say Say Say'' (duet with Paul McCartney) 12 The Supremes ``Love Child ''Madonna`` Like a Virgin'' 11 Whitney Houston ``I Will Always Love You ''10 Stevie Wonder`` Ebony and Ivory'' (duet with Paul McCartney) Janet Jackson ``Miss You Much ''
Document 10: Madonna (entertainer): In Evita (1996), Madonna played the title role of Eva Perón. For a long time, Madonna had desired to play Perón and wrote to director Alan Parker to explain why she would be perfect for the part. She said later, "This is the role I was born to play. I put everything of me into this because it was much more than a role in a movie. It was exhilarating and intimidating at the same time..... And I am prouder of Evita than anything else I have done." After securing the role, she had vocal training and learned about the history of Argentina and Perón. During shooting she became ill several times due to the intense emotional effort required. However, as she told Oprah, she was also pregnant during the filming: "I was winded after every take. I had to lie on the couch every ten minutes so I could recover from dizzy spells, I was worried that I was shaking the baby around too much and that would injure it in some way." Madonna wrote in her personal diary at the time: "Ironically, this feeling of vulnerability and weakness is helping me in the movie. I'm sure Evita felt this way every day of her life once she discovered she was ill."
Document 11: Madonna (entertainer): Madonna holds the record for the most number-ones on all combined Billboard charts, including twelve number-one songs on the Billboard Hot 100 and eight number-one albums on the Billboard 200. With 45 songs topping the Hot Dance Club Songs chart, Madonna became the artist with the most number-one songs on an active Billboard chart, pulling ahead of George Strait with 44 number-one songs on the Hot Country Songs chart. She has also scored 38 top-ten singles on the Hot 100, more than any other artist in history. In 2008, Billboard magazine ranked her at number two, behind The Beatles, on the Billboard Hot 100 All-Time Top Artists, making her the most successful solo artist in the history of American singles chart.
Document 12: Madonna (entertainer): Possessing a mezzo-soprano vocal range, Madonna has always been self-conscious about her voice, especially in comparison to her vocal idols such as Ella Fitzgerald, Prince, and Chaka Khan. Mark Bego, author of Madonna: Blonde Ambition, called her "the perfect vocalist for lighter-than-air songs", despite not being a "heavyweight talent." According to MSNBC critic Tony Sclafani, "Madonna's vocals are the key to her rock roots. Pop vocalists usually sing songs "straight," but Madonna employs subtext, irony, aggression and all sorts of vocal idiosyncrasies in the ways John Lennon and Bob Dylan did." Madonna used a bright, girlish vocal timbre in her early albums which became passé in her later works. The change was deliberate since she was constantly reminded of how the critics had once labelled her as "Minnie Mouse on helium". During the filming of Evita, Madonna had to take vocal lessons, which increased her range further. Of this experience she commented, "I studied with a vocal coach for Evita and I realized there was a whole piece of my voice I wasn't using. Before, I just believed I had a really limited range and was going to make the most of it."
Document 13: Queen (band): Queen began their 1980s career with The Game. It featured the singles "Crazy Little Thing Called Love" and "Another One Bites the Dust", both of which reached number one in the US. After attending a Queen concert in Los Angeles, Michael Jackson suggested to Mercury backstage that "Another One Bites the Dust" be released as a single, and in October 1980 it spent three weeks at number one. The album topped the Billboard 200 for five weeks, and sold over four million copies in the US. It was also the first appearance of a synthesiser on a Queen album. Heretofore, their albums featured a distinctive "No Synthesisers!" sleeve note. The note is widely assumed to reflect an anti-synth, pro-"hard"-rock stance by the band, but was later revealed by producer Roy Thomas Baker to be an attempt to clarify that those albums' multi-layered solos were created with guitars, not synths, as record company executives kept assuming at the time. In September 1980, Queen performed three sold-out shows at Madison Square Garden. In 1980, Queen also released the soundtrack they had recorded for Flash Gordon. At the 1981 American Music Awards in January, "Another One Bites the Dust" won the award for Favorite Pop/Rock Single, and Queen were nominated for Favorite Pop/Rock Band, Duo, or Group.
Document 14: Madonna (entertainer): Life with My Sister Madonna, a book by Madonna's brother Christopher, debuted at number two on The New York Times bestseller list. The book caused some friction between Madonna and her brother, because of the unsolicited publication. Problems also arose between Madonna and Ritchie, with the media reporting that they were on the verge of separation. Ultimately, Madonna filed for divorce from Ritchie, citing irreconcilable differences, which was finalized in December 2008. She decided to adopt from Malawi. The country's High Court initially approved the adoption of Chifundo "Mercy" James; however, the application was rejected because Madonna was not a resident of the country. Madonna appealed, and on June 12, 2009, the Supreme Court of Malawi granted Madonna the right to adopt Mercy James. She also released Celebration, her third greatest-hits album and final release with Warner. It contained the new songs "Celebration" and "Revolver" along with 34 hits spanning her career. Celebration reached number one in the UK, tying her with Elvis Presley as the solo act with most number one albums in the British chart history. She appeared at the 2009 MTV Video Music Awards on September 13, 2009, to speak in tribute to deceased pop star Michael Jackson.
Document 15: List of Billboard Hot 100 chart achievements and milestones: Number of singles Artist 38 Madonna 36 Elvis Presley † 34 The Beatles 31 Rihanna 29 Michael Jackson 28 Stevie Wonder Mariah Carey 27 Elton John Janet Jackson 24 Drake
ground_truth: May 1997
sub_queries: who had the most uk hits in the 80s Answer: Madonna
When did Madonna 's relationship with Carlos Leon ended? Answer: May 1997