My girlfriend cheated on her ex. Does that mean she'll cheat on me too?
While I’m not saying your girlfriend cheating is a good thing, but like all of us, she’s only human and prone to errors. Also, people cheat for a variety of reasons, such as not being emotionally fulfilled. I suggest you tell your girlfriend you know a) she’s human, b) she has learnt from her past, and c) you trust her. Showing this compassion and love will strengthen the bond between you.