I'm looking for a story (probably LW) about a male MC, who has a girlfriend and I think becomes his fiancee. She finds a side piece, and takes him to South America (Jamaica?) for a week vacation. I think the MC was supposed to go but he discovered the cheating and did not want to go. While she is gone, MC gets gets all things, gets all her things, moves out, goes to her mother's house to give the stuff back. He finds out from her mother that her husband left her for someone else and then those 2 spend a weekend having lots of sex, before MC leaves for good. The mother even says something like "Like father, like daughter".