Conversation so far:
Who did Abby Newman have a romance with?
Daniel Romalotti.
WHat are some details about their relationship?
Abby and Daniel's relationship was outed when Nikki Newman and Daniel's mother, Phyllis Summers, saw Abby and Daniel making out in public.
Did they break up?
when Abby found out that Daniel fathered a child with Daisy Carter, she broke up with him.
Who was next boyfriend?
Marco Dapper's.
Did they stay together?
However the relationship wasn't given closure upon Rylan's exit from the soap opera.

Question: Why did the actor playing him leave the show?
Self-contained rewrite: Why did the actor playing Marco Dapper leave the soap opera?