How you guys still like Stacy after this??

I stopped watching after watching Stacy cheating on Mark kissing House. It's fucked up thing. But no one seems to care. I tought she was going to stay loyal. It must be hard for mark trusting Stacy in staying next to her ex and she cheats on her like that. I know they had an argument, but that is not a excuse to me. How the series take this as some romantic shit? What do you think?