If I told him he was abusive towards me he would genuinely laugh as he seriously sees nothing wrong with anything he does.
I'm sure he would. Abuse is hugely psychological and requires him to convince you that you deserve what's happening, that you are overreacting, that you make him do it, that he is not doing anything wrong.
None of those would be possible if he admitted it, would they?
I once asked my abuser in desperation mid-explosion why he was doing that to me, and he laughed in my face and told me how much worse he could be if that was what I wanted.
They do genuinely know how awful they are, but that doesn't mean they will accept it. In addition to the reasons above: it's a crime, people rarely admit to crimes; and secondly all humans have a need to believe we are good people, none us copes well with the idea that we are not (look how ill people become who believe that they are bad - depression etc) and admitting to being abusive would disrupt his ability to maintain his internal sense of being good.
The guilt will not destroy you.
The day I left it was so overwhelming I felt physically ill and dizzy. I almost didn't leave because of it, but as soon as I was away it began lifting.
The only person who should feel guilty is him. The abuse has transferred his guilt onto your shoulders. Give it back to him mentally and do what is right for you.
Your relationship history suggests you may not have the best sense of what a healthy relationship looks like in the first place. (I'm not judging, I was the same). Regardless of whether you manage to leave or not, the Freedom Programme will help you understand the difference between a healthy relationship and an abusive one. As well as the impact it's had on you and why you're tying yourself in knots. It will give you the tools to have healthy relationships in the future.
It's free to attend, they don't keep attendance registers, nobody will know you've gone, lots of them have creche facilities, it's confidential. My group also always had cake or biscuits in the break each week. (It was a 2 hour session, once a week for twelve weeks.)
It's not therapy, it's information. They're small groups of women, you don't have to talk and share your experiences, you can just listen. They won't judge you, and they won't tell you what to do - they want to give you information, help you to make sense of it, and then give you the power to make your own decisions.
Www.freedomprogramme.co.uk
They have a phone line and an email address if you want to talk to somebody there.
It's understandable to feel conflicted, but be aware that will only lift once you're removed from the situation. It's incredibly difficult to get any clarity or stability when you are still being abused. It would be like expecting a burn to start healing while you were still holding your hand in a flame.