I had a wonderful boyfriend and all the sudden I got a screenshot on Instagram from a random girl. My boyfriend was sending pictures of his dick to her. He says he's so sorry, but it's my fault because he's sexually frustrated. He knows I'm a virgin and I'm not comfortable with everything. We've even had anal sex before. So it's not like I'm not giving him anything. I consider that cheating, offering yourself to someone else. He lies and goes behind my back. He won't listen to no, he'll keep doing what he wants even if I say no. One time he would not listen and he says he basically raped me and he felt so bad about it. What should I do? Should I forgive him?