Me (22F) and my ex (25M) have been working together for 5 years. Dated for the first three years only to find out that he cheated on me for 1.5 years out of the 3 years. I met the girl, she didn't know about me, we confronted him, the only excuse he had was that he wanted to breakup with me but didn't have the guts too and didn't want to hurt me. Me and the girl both broke it off with him. He kept begging both of us lol to get back together. The girl however had to move to another city for a job posting and I don't know if it was insecurity or something she got back together with him. We were still working on the same office project and ended up sleeping together. Decided to make a pact to keep on doing so until the end of our office contract which was in 2 years. Throughout this time he was with the girl he cheated me on with. Him and I would go for lunch dates, talk on the phone, joke around and basically do everything together. He would even get mad if I hung out with other random guys. Howver now that the office contract is coming to an end, I feel that it is so mucb easier for him to let go of me than it is for me. No matter what he says or does, I don't get mad at him. I just can't. May be it is love. I really don't know. All I can think of is that he is a good person who got into this situation because apart from his personal life he actually is a kind person. But it's important for me to hate him or get angry at him for hurting me to move on. I just need to get over him. Any tips/suggestions will be highly appreciated.

TL;DR - got cheated on my by ex, stayed friends with benefits with him for 2 years while he was still with the other girl, can't move on. What do I do