Why can’t I 24f leave my husband 25m after finding out he cheated?

My husband 25m cheated on me 24f and I don’t know why I can’t bring myself to leave.

We’re coming up on a year of marriage. I recently found out that while I was pregnant and also postpartum, he was sexting and sending nudes to his ex. It wasn’t physical as far as I know, but it was intimate and sexual and it feels like cheating in every way that matters. it happened before we got married, and he still chose to marry me while hiding it. He continued to lie about it for almost two years. I only found out because I went through his phone. If I hadn’t, I would probably still have no idea.

He swears nothing physical ever happened and that there’s nothing else. But how am I supposed to fully believe that when he was able to hide this so well? The betrayal feels even deeper because I was pregnant and then newly postpartum when it was happening. That was such a vulnerable time for me.

At first I was strong about it. I told him I didn’t want this and that I deserved better. But then reality set in. We made vows. He’s the father of my daughter. We have a whole life intertwined. It’s not as simple as walking away.

I get so much mixed advice. Some people say leave immediately. Some say marriages can survive this. What I know for sure is I will never love or trust him the same way again. Something in me shifted. Even when we’re okay, it’s always there in the back of my mind.

The hardest part is how back and forth I am. One minute I’m forgiving him, we’re being loving and intimate on and it almost feels normal again. Then I snap back to reality and feel disgusted with myself for letting it be normal. I tell him and myself that this can’t happen. Then the cycle repeats. It makes me feel weak and pathetic because I always said I would never stay with a cheater.

A huge part of me thinks this is already over and I’m just delaying the inevitable. But another part of me is clinging to what feels familiar and safe and hoping somehow it can go back to what it was.

I feel stuck and honestly just heartbroken. I don’t know if staying makes me strong or stupid. Any advice would really mean a lot right now.