Boyfriend cheated on me for a year, should I forgive him?

(Some background info: me and my boyfriend had been dating for almost three years when this happened and had lived together for almost a year and a half, as well.)

About a month and a half ago, I found out my boyfriend of almost three years was cheating on me by sexting and calling different girls. He was in contact with about 5 or 6 other women... some of that content was explicit, as in they would send him nudes. Some of these women he actually knew in person... Two of them are from the same city as us, and ONE of these women was an old coworker. I broke up with him when I found out, but we continue to live together and he insists over and over that he wants to win me back and love me right this time.

The thing is, talking to him yesterday he finally revealed it wasn't just messages. He kissed his coworker about a year ago, he said. He claims this is "ALL THAT HAPPENED", but I'm skeptical. It's shady that he lied about doing any physical cheating until now...

Going through his phone last night was heartbreaking. He was always hitting her up (usually late at night) about getting together and hanging out, and even though he swears nothing else happened, I have confirmed he left his coat and shirt there once and it took him a while to get his clothes back from her.
It seems weird to me that he kept in contact like that and they only kissed once, because they kept talking throughout the year he was cheating on me.
Am I being crazy in suspecting they fucked?
Also, should I even be considering letting this person back in my life and giving them a second chance?

(sidenote: he deleted all of their contact info but for some reason still hasn't deleted their messages?)
Boyfriend cheated on me for a year, should I forgive him?
Add Opinion