I don't think he's *just* stupid, eve stupid people know that sleeping with your friend's gf is bad but for stephen it's ok. :/
But she? I don't think I knew any other female character i'd hate so much. She's just awful. And if she'll be a leader I feel sorry for TP.
In general I just want Stephen and cara to be together and stop torturing poor john and for john to find a decent girl and forget about that bitch.