Complex sentence: Passions between Heseltine and Puma had meanwhile cooled; when she became pregnant, Heseltine confided to Delius that he had little liking for the ex-model and had no intention of helping her to raise this unwanted child.
Split into simpler sentences: Passions between Heseltine and Puma had meanwhile cooled; an unwelcome complication was manifested when Puma became pregnant. To Delius, Heseltine confided that he had little liking for the ex-model and had no intention of helping her to raise this unwanted child.