Oscar and Jessica started dating each other at a certain time in college. Sometime after they graduated, the two of them broke up because they began growing apart. Shortly afterwards, Oscar found out that he was gay and started going out with his long-time friend Louis, even though Louis had no idea they were dating. It is unknown what Oscar's reaction was to Louis getting together with Jessica and eventually marrying her, but he most likely didn't care. It wasn't until he came to visit them in the events of the episode, when Jessica found out he was gay and Louis figured out, they were dating for a while.