From IMDB:

Movie star Ben Affleck has vowed not to marry his superstar fiancee Jennifer Lopez until media interest in the couple’s wedding wanes. The Jersey Girl co-stars were due to tie the knot in September but called off the wedding at the last minute blaming excessive media attention. And now laid-back Affleck has decided to wait as long as it takes for people to forget about the couple before making the Out Of Sight beauty his wife. He says, “Who says there’s a rule we gotta get married right away? That’s my plan - to go along and be unmarried until it stops being an issue. Look at Kurt Russell and Goldie Hawn. We’re really not in any rush.”