Complex sentence: It is believed that Hendrix and Betty Davis had an affair that hastened the end of her marriage to Miles Davis, but Betty denies this and Hendrix and Miles stayed close after the divorce, even planned to record until Hendrix's death.
Split into simpler sentences: It is believed that Hendrix and Betty Davis had an affair that hastened the end of her marriage to Miles Davis, but Betty denies this. What's more is that Hendrix and Miles stayed close after the divorce, even planning to record until Hendrix's death.