Questions: Break Up & Divorce

Me and my boyfriend have been together 3 years. I have had doubts about his best friend who is a girl but i have always trusted him so decided to leave it be. However, we recently broke up and got back together within a week. I found on his phone (I had to use it due to mine being out of battery) that he had gone to her house and they had sex as soon as we broke up. He denied it to the last until I told him I saw the texts and he admitted everything. I have sacrificed so many friendships for this person and he has betrayed me in the worst possible way. Any time I look at him all I can imagine is her and him together? I don't know what to do at this stage, my friends and family hate him and have told me to block him but there's still feelings there and we both have tattoos of each other's name so I feel like we have to be together now which is stupid I know.

My ex and I split up a month ago and he's come back to say that he wants us to try again and that he needs to be honest before we say any more. He then told me that he had one night stands with other people in that time.

Part of me thinks, ok so he was single but the other part of me thinks so whilst i was at home feeling so much heartbreak you were out getting it on with someone else. Fuck you.

I'm trying to decide between don't ever speak to me again and ok you can take me on a date.

I feel like an idiot.

What would you do and what's your opinion?