do you forgive him?

I started to freak out and told him I still wanted to talk but be closer to friends for a while because I wanted to build a foundation first for our relationship. That weekend I then went out of town. While he went out with my friends all weekend and continued to send me updates and snaps I was busy with family and a school assignment so I wasn't texting back very often. Saturday night he went to a party where a girl was all over him. He kept trying to get rid of her the first half of the night (heard this from trust worthy friends) but as he got black out drunk he made out with her. I then found out from a friend the next night and when I confronted him he admitted immediately. 

Should I ever forgive him? 

Before this he never ignored me or treated me wrongly at all.