The whole point of the cheating subplot is to show you they weren't a great loss to her because they weren't great friends. You have a boyfriend who is cheating on you with your best friend and they are nice to your face but not behind your back !! They also steal each others credit cards at the beginning to pay for crap!! Good friends don't do that!When her cousin decides to "do his thing" you don't miss them!! It also goes for her decision to back up her cousin at the end! Family is #1! That was the whole plot of the movie! Friends come and Go but family is more important!