Why did he lie about his ex? my heartbreak story

I've been with my boyfriend for four months but the beginning of our relationship has left me questioning everything.
When we first started talking I had no idea he was in a relationship. We were long distance and spent months talking every day staying up until 2 or 3 in the morning playing games and sharing everything with each other. He constantly told me how amazing I was how much he cared about me and eventually I fell for him. Then I found out he had an 8-year girlfriend he was living with.
I felt completely blindsided. Having been cheated on before I wanted to walk away immediately. He told me he had already checked out of that relationship emotionally that he planned to end it and that what we had was different. He said he wanted a future with me.
Not long after he came to visit me. He told me he and his girlfriend had broken up and during that visit we became intimate. He reassured me over and over that I was the only person he wanted. But when it was time for him to leave he admitted he hadn't actually ended things with her yet. He promised he would do it as soon as he got home.
I felt awful but the next day they broke up she moved out and eventually we started dating officially.
Since then our relationship has been loving and supportive. He visits me every weekend is thoughtful and affectionate and has always reassured me whenever I felt insecure about his ex and their long history together.
Then four months later I reached out to his ex.
That's when I learned that after visiting me for the first time he went home and slept with her. He had told me multiple times that nothing happened between them. According to her they were intimate and even cuddled afterward.
What hurts most isn't even what happened. It's that he lied to me about it for four months. He looked me in the eye reassured me and let me believe a version of events that wasn't true.
When I confronted him he admitted it happened. He said he regretted it that he wasn't strong enough to stop it and that he kept it from me because he knew I would leave if I found out. He said he wanted the past to stay in the past.
His ex also told me that when they broke up the next morning he was crying hugging her kissing her goodbye and struggling to let go. He says it was because the end of an eight-year relationship was a huge life change.
Now I'm stuck between two realities. On one hand our relationship has been good and I love him. On the other the foundation of our relationship feels built on lies.
I can't stop wondering how someone could tell me they loved me spend time with me then go home and be with someone else that same day. The deception is what hurts most.
Am I overreacting for feeling betrayed? Can trust ever fully come back after something like this?

Last updated on:2026-06-23T18:17:12+05:30