Shawn tells Cory he has to get back together with Topanga, "Because,
you know, someday, after a slew of meaningless relationships, it's possible that I'm gonna want what you have." But Shawn is already in a serious relationship with Angela, and there have been multiple instances already where he is explicitly trying to emulate Cory and Topanga. (Angela is inexplicably absent from this episode and is never mentioned.)