Summer is a lesbian
She had already experimented with women (like Charlie), but it took Toom to finally let her see that she's not cut out for men. Tom thinks that she has married a man never actually sees her husband. And as for the scene at the bench, fans already say it was just Tom's fantasy. And the proof that Summer is a lesbian? She once greeted Tom "Hey" and not "Hi", just like Paul said a lesbian would.
