I am in a long distance relationship and my girlfriend recently admitted that she had cheated on me. She said, and I believe her, that she really loves me and that this was a mistake she regrets. However, I can't take it out of my mind and forget about it. I am angry that she ruined the purity of our love story. It feels like it's no longer "a dream come true" — merely a watered down version of it because it is no longer "flawless." I feel like a pushover for not doing anything about it. (I'm really in love with her and I can't bring myself to break up just for that.) How can I forgive her? Will I always keep these poisonous thought inside? How can I prevent this from shadowing every aspect of our relationship? Am I "selling short" and blind to her untrustworthiness? How can I trust her again?