Husband cheated before engagement. Leave or stay?

Timeline - We started dating in May 2017 while in graduate school in different cities. In Feb 2018, he moved to another city for a job. He had another female friend from his school join the same company and since they were friends already, they hung out a lot. This female friend had a crush on him since school but she was dating someone else(Mr.A) and he was dating me. In Mar 2018, barely a month after moving, they shared a kiss.My boyfriend told me, we had huge fights, but he said its a one-time thing and nothing would happen and they are just friends and he wants to be with me etc etc. I did not leave him at that time but I never ever liked that girl and their friendship. It was just so uncomfortable to know that they are hanging out all the time. However, time went on. We got engaged in Jan 2019 and married in Jan 2020. Current situation - Recently in 2021, due to some turn of events, husband confessed that the two of them had sex throughout 2018. A lot of times it was after getting drunk on a Friday/Sat night, a lot of times it was in a sober condition as well. That girl used to come over to his apartment at night, in need of company, being all sad and shit and he would let her in. There have been times where he said that he let her slept over but nothing happened between them as he refused all advances. She once came over crying, begging him to leave me, citing things like "I have never been in this position that I want a guy and I have not got him and that is messing up with me". All this while, he was dating me and she was dating the other guy(Mr.A). In 2019, after we got engaged, he started distancing himself from her. Stopped hanging out, stopped responding to her calls. We still used to hang out as a group, Mr. A and me being unaware of their escapades. The last time they did it was in Dec 2018 which was not even a month before our engagement date. Nothing happened in 2019. Now, my husband says that there was never a good time to tell. He did not have the strength to tell me for the fear of losing me. He knew I would walk out. And everytime they had sex, they had a period of not talking to each other but he went back thinking that it wont happen again and they will be back to being friends. Whenever he had a conversation with that woman, she would not say anything, would just make a face but not participate in a conversation. And since Jan 2019, he realized that she will never be the friend he was looking for, realized he did not need her, and stopped talking to her one-on-one. It was only in groups, in the presence of her bf(Mr.A) and me. All this is very overwhelming, hurtful, utterly disrespectful for me. I had let go of that one incident I knew about, I thought we have a healthy relationship and that is the reason I got engaged and eventually married to him. While he says that he could have left me for that woman, but he did not because he wanted me. He was never attracted to her and all that happened was just unemotional sex(I dont believe that thing exists). I have started doubting if I even love him. My life could have been so much different if I had left him in 2018 right after the first act. I feel so sad, angry, hurt all at once. I dont know if I should stay, give him another chance given the fact that he was loyal after we formalized our relationship, or leave? Please advice.

Personally, I would leave. Once a cheater always a cheater. He only needs an excuse...as he has shown with the whole "I was mad when it happened and though it would never happen again and again and again and again etc". And not only did he cheat for roughly a year, but he lied about it for 2 more years and waited til you were legally bound to him before telling you. You're marriage is based on lies. Because you never would have married him, if he had told you the truth. And that says it all.

"All this is very overwhelming, hurtful, utterly disrespectful for me." Yep. It was. Do you want to marry someone who choose to hurt and disrespect you? (I would not.) And if he's willing to blow up your relationship for unemotional sex with someone he's not attracted to, just imagine what he's willing to do if he's given the option to have emotional sex with someone he *is* attracted to. I don't know that I'd say, "Once a cheater, always a cheater" (people *can* change, although it's rare), but he does not seem like a good guy from this story. Why tie yourself to someone like that? Find someone better. *virtual hugs*

Yes, he has been faithful to me since we got engaged in 2019. To the extent that the he distanced himself from her and slowly completely stopped talking to her. It came out now because I texted her bf and told him about the kissing incident. I was frustrated how she was not held accountable for anything and I was considered the evil person, the jealous gf, in the group because other people thought I was the one who caused them to stop being friends. Her bf then broke up with her and she came back to me playing the victim card and saying I broke her relationship and there were more things that happened that I dont know and that is when my husband confessed. Another point about that girl, once my husband started distancing himself in 2019, she started sleeping with another of her office colleague behind her bf's back. I feel she is just one of those girls who knows how to get guys to do things for them and my husband got entangled in her manipulations? In total, she has made out/slept with 3 other guys while having a public bf throughout. My husband was the only one who was in a relationship, the other 2 guys are single and dont have anything to lose. I really think we should go for counseling, thanks for the idea.

"I was frustrated how she was not held accountable for anything" But why should she be? She's not the one who promised fidelity to you. (That would be your finance.) If she annoys you, ignore her. You don't *have* to deal with her. So what if she cheats on her boyfriends? That sucks for them, but it's not *your* issue. Give yourself the gift of not caring about her or the train wreck of her life.