Find out my girlfriend of 5 weeks cheated on me with her ex boyfriend of 7 years should I forgive her?

Anonymous
So last night I got a video chat from my girlfriend phone and I answer it my girlfriend was being fucked from behind by a black guy. My hurt started to race but then during the video chat he was saying random things to her like who has the best dick she said he did and that she was his wife that she will marry him and that this isn’t the first time she had sex with him in the 5 weeks that I’ve been dating her. I blocked her on all social media but then she texts me saying they both were drunk and that she wants me to forgive her should i? I have repeated told her I didn’t want her talking to her ex boyfriend for the past 4 weeks only to find out she still was behind my back.
Find out my girlfriend of 5 weeks cheated on me with her ex boyfriend of 7 years should I forgive her?
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