Why am I finding this so difficult?

[FindingSerenity]

I was in a relationship with someone following the breakdown of my marriage. It was a relatively short relationship although I knew him for a while. By and large, the person was not who I thought they were and they treated me badly. I was in a vulnerable place and I believed they were a light in my life. This person showed me attention and affection and promises of a future. Relatively quickly there were red flags and I ignored them all because I thought the good seemed to outweigh the bad but when I reflect, the lows were so extremely low that I'm not sure if the highs were really high at all. Or just a calm normality following a bad episode. It became quite emotionally abusive: a lot of paranoid jealousy, accusations of all sorts and a very bad temper. I walked on egg shells and ironically, I probably felt the need to try harder than what I ever did in my marriage just to keep things on an even keel. I've accepted that the way I was treated was wrong on many levels but he fully believes he did nothing wrong. That I was simply treated in accordance with what he believes I did. None of which I actually did.

So, please, I just need help understanding after everything that this person put me through (there's a lot), why do I miss them or miss the 'good'? I've went NC. It's been a few weeks. Why do I feel like I'm physically struggling? I am really trying. I just want to be me again.

but he fully believes he did nothing wrong

This type never do and they never will.

On some level if you were pretty deeply bonded to him you might believe his BS too and from my experience of that, breaking down the delusion of who he was and who you were in the situation is key to moving past it. It can be very traumatic though because you can strongly feel that you can’t trust yourself and you need to build that trust back up.

I was in a vulnerable place and I believed they were a light in my life. This person showed me attention and affection and promises of a future.

That's why you're struggling. The behaviour above is often known as "love bombing" and it's favourite tactic of abusers to make you fall hard and fast in love, and keep you hooked. It's like having a hit of opiates - all your pleasure centres in the brain respond, and you keep chasing that dopamine hit.

But the image he painted of himself in that first period of getting you hooked was not the real him. The real him is the abusive manipulator you've now seen. That loving, caring man he pretended to be - doesn't exist.

It sounds like you're still in contact with him? I would suggest blocking him on everything. It's the only way.

I feel for you. After the end of a marriage the first relationship you enter into can be hard to navigate, especially when you are very quickly loved bombed, shown affection and attention and given promises of a rosy future together.
This is 'future faking' and can be all part of a plan to you manipulate you, especially as you admit you were in a vulnerable place. Too much attention too soon is not a good thing, and is often quickly followed by controlling behaviour to wrong foot you and draw you into the pusue - withdraw cycle, so you feel confused and ever eager to please.
If you are still in touch with him the best thing that you can do to protect yourself is to break ties and go completely no contact. Otherwise you risk being drawn back into what is an unhealthy and toxic relationship.

Because he wasn't 'putting you through it' 100% of the time, and you were strongly attached to certain aspects of him and the relationship.

There's no rocket science, here. Somewhere, most likely in your childhood, via your parents, you've learned that 'love' involves someone treating you respectfully sometimes, and having to overlook the times they don't treat you well. You've simply replicated that. And now, after having a relationship that was like 'home' was for you as a kid, that's the craving you have to see him: you want to go 'home'.

It's time to create a new version of what a healthy relationship looks like. The truth is, it feels loving and supportive pretty much all the time, even if you fall out a bit sometimes. There's no 'overlooking'. The first health relationship to develop is with yourself. You have to have a relationship with yourself that feels loving and supportive, pretty much all the time. That means that, like with a child, if you find yourself often feeling bad when you spend time with someone, you stop spending time with them, even if you really love them, and it's fun to see them. Just like if a child had a friend who was nice to them 90% of the time, and used the other 10% to bully/criticise/taunt them, you wouldn't let the child keep seeing that friend.

Don’t beat yourself up OP. You have shown how strong and brave you are by leaving the nut and then going nc. You need time to think about what you want from life and how to get it. It’s hard now, but things will get better with time.