I have been seeing my BF for a little over a year. When we first got together it was a hard time in my life. Custody battles with my ex, needing to make sure my daughter was safe, etc. I wasn't able to be with him all the time. We had been dating for about 5 months when I found out he was playing around. I just recently found out on my birthday that he had slept with another girl one night after he got off work. It has taken so long to finally get him to admit the truth to me. We're talking almost a year, although I knew the entire time. I know he's remorseful. He beats himself up for it every day, and every day he asks how he can earn my trust again. I want so badly to forgive him, and I've tried many, many tools to make it easier in both of us. We talk, but it's starting to feel like we can't get anywhere. He's patient, but I have to be honest. I am so scared he's going to do it again, or is, and I am not sure if it's my gut, or just the fears clouding my proper judgement. I do love him, he's my soulmate. And I do know we can work through it... what am I doing wrong?

NOBODY is anyone's soulmate. Once you understand that, you'll be better off.

Ok, so sure, you say he beats himself up over it every day but does he really? I doubt it. Nobody cheats by accident and if he did it, then it was by choice... so it couldn't have been too bad. So you can't trust him and you want to know what to do about it...

In all honesty, break up with him. If you can't trust him now and this amount of time has passed, you will never be able to trust him. This is ruining your relationship now and there is no easy answer. I understand why you can't trust him and I wouldn't either. Like I said, it's not an accident and it was a conscious decision on his part... he knew what he was doing... then he wouldn't admit it to you even though you knew... doesn't really sound to me like he is sorry at all... only sorry that he got caught... that's it.

So deep down you feel you can't trust him and you don't know how to get over it. You won't. Obviously there are still things going on that make you doubt him.

Save yourself and break up... things are not going to magically improve.

I can't even say that it's the stuff he did that I dwell on. What's bothersome to me is that I can go long periods without thinking about it, or talking about it, and then something happens that brings the fears up anew. Like if he doesn't let me know when he's headed in from work, and just shows up at the house, or says that he told me something in particular and I swear he didn't. But the whole thing is, I WANT to forgive him. I love him. I don't want this haunting us. It's the past. But there's always something that will bring the subconscious fears to surface, and it's all completely uninvited.

I'd like some more clarity.
You've been dating a little over a year.
He cheated one night after work about 5 months into the relationship, and he had been 'playing around' before then, while you were busy dealing with your ex.
You knew about the playing around, but not the one night stand, which you found out 'on your birthday' (?) and yet somehow 'knew' all along?

From the way you write, it sounds like you want to forgive him because you couldn't see him much for the first 5 months. We don't know how many times you were dealing with your ex and how he construed all that. We don't know how 'seeing' him as you say really counts as an exclusive relationship. Did he ever wonder if you were sleeping with your ex? That's a common fear, even when it's clear that you can't stand the ex.

If you do want to solve this, you can only do it by sitting down and have a serious talk with him about each little detail of your fears. E.g. I can't fathom why you would be suspicious if he 'just shows up at the house' after work, without calling - that means he was having a quickie on the way? (Makes no sense to me) Tell him what you said here; that it surfaces when things are going wonderfully or without reason. Let him talk. Do this several times over several nights or even weeks. If it doesn't solve anything, get couple counselling.