So just to add some background info: We met through tinder and I was her first. A few weeks in, she admitted to liking me so I agreed that we start to go dating. Aftwards, when when we were then seriously dating at the time, going on dates and saying "love you" every night. Out of the blue, she suddenly told me that she was gonna go clubbing with some of her friends. I didn't think too much anout it at the time as I trusted her. The day after, she messaged me and everything seemed normal.

A few months after we were officially a couple, she admitted that she lied. According to her, she went alone with a guy friend she trusted. She left her I.D at her house and hence was denied entry. The guy was pissed so she felt guilty and followed him home. She then said that the guy and her were drinking and he suddenly kissed her, then it happened.

I was really hurt about this, but I tried understanding her. I still had some doubts though, so I snooped around her email and facebook. I'll spare the details of how I did it, but I confronted her about the guy, asking if she really was his long-time friend. She confessed that she met the guy through tinder. According to her, she first met him shortly after first meeting me. As according to her, she felt at that time that I was only in it for sex, so she felt hurt. They went out and then did it that night at a hotel the guy booked. She told me that she told the other guy that she was already seeing me, but she didn't tell me about the other guy. The guy was mad and demanded her to stop meeting me, to give him a chance. However, she found him to be a douchebag, so she kept seeing me instead. However, she still kept in contact with the guy while we were seeing each other, and then one time, the guy asked to go clubbing with her one last time as he was about to leave the country. Then it happened wherein she left her I.D so the guy got mad and she felt bad so she followed him home. However, in her latest "confession" she said that when they were in the guy's room, she said that she told the guy that she was about to leave but he got mad and pushed her to the bed. They did it but midway she didnt want the guy to come and gave him a blowjob instead.

My question is, is it right for me to feel angry/betrayed and somewhat disgusted with her? If what she said was really true, why did she follow the guy into the car? Why did she go into the guy's room? Did she really think it was ok to go alone with a guy whom she had past sexual relationships with alone to a club? She told me that she didn't want the guy to get mad at her, that was why she followed him. But having had a sexual past with the guy, she must have fully knew where going home to the guy's place would end in. I've tried forgetting about it but the issue keeps making me angry, I've gotten mad at her and called her names. I think that I loved her before, but all this feeling of pain and betrayal robbed it away.