Complex sentence: Anthony had a cradle-snatching relationship with Albert Square's resident teen Zoe Slater; unsurprisingly the relationship fell through after Anthony realised he still loved Zoe's mother Kat who he had dated previously.
Split into simpler sentences: Anthony had a cradle-snatching relationship with Albert Square's resident teen Zoe Slater. Unsurprisingly, the relationship fell apart when Anthony realised he still loved Zoe's mother, Kat, who he had dated previously.