I'm so sorry you are going through this, I've been there myself and I wouldn't wish the pain on anyone.
He's made me feel like a fool. And little things like he's been buying lots of new clothes lately, my suspicion is he's looking for someone else but doesn't want to end until he finds someone, but he'll just deny that
Focus on this and find your anger. This is what he has done to you, he has made you devalue yourself and lose your self worth. Do you think someone who makes you feel this way deserves to be with you? Do you think that's all YOU deserve?
it was just for attention and he wouldn't act on it
This was the EXACT excuse (pretty much word for word) I got from my husband when I caught him on fabswingers. Trust me, they only ever admit to as little as possible, they will minimise the hell out of it. I'd seen messages between him and someone discussing dates they were free, he was talking about how he would usually need to meet up out of the house but he would occasionally be able to accommodate (as in, fuck someone in OUR HOME). That much detail, but he was apparently never going to go through with it.
That was 2.5 years ago now, I had a long running thread on here at the time with most people telling me to leave because I'd never trust him again, I really wish I'd listened. When you stay it just eats away at you, you may begin to feel like you have a little bit of trust for them but it's always there in the back of your mind because you can never unsee what you saw, you will now always know just what they're capable of. I'm in the process of splitting now, I wish I'd done it when I first found out but sometimes you have to make your own mistakes before you realise what you need to do.
The thing that really stands out to me here (and did in my own situation) is the constant minimising and lying. Maybe if he'd come to you, owned up, accepted what an awful thing he'd done and thrown hmself into trying to make it right, then maybe there would be a chance of working it out. Instead he's lied to you, even after you saw what you saw he still tried to say you were wrong! That's gaslighting. Now he's minimising it and saying he didn't cheat, you're making it sound worse than it is, etc etc. He's a lying POS. You don't have to put up with this shit and spend your life wondering if you're good enough (you are, by the way).