im so angry at myself for letting this happen & I struggle so bad with feeling like it’s all my fault, I think that’s why I let it go on for so long!
You were groomed. He started off nice, testing you with red flags so tiny you either wouldn't see them or would think you must be mistaken because he's so nice. Once you are hooked, then he can start his business in earnest. That's when he starts blaming you, making you doubt yourself, persuading you that he's a victim. And he just keeps ramping that up until you are a shell of your former self. It's what they all do, those that are so special and wonderful - the reality is they know they are so weak and insignificant they need to bring you down to make themselve feel better. It is not your fault, you didn't have a choice, he groomed you into taking what he gave out. You are out now, that's the main thing 
I want to stop going over in my head everything that has happened, accept it for what it was (abuse I did not deserve) and make positive changes in my life, I know I can do it but I’m so scared of feeling like this forever
It would be so good if the end of an abusive relationship was just "Right, that's that" but it's not. It takes a lot of healing from. They have done a lot of work on destroying you mentally and quite possibly physically (even if he wasn't physically abusive with you your body might be affected by what he put your brain through). All the things you thought were true were lies, you've had a whole lot of headfuckery for however long, you need to work through that to tidy it up in your head and box it up to eventually be covered in dust and cobwebs.
You could try writing down these thoughts when they come into your head. I've got pages and pages of rantings from the early days, letters to him (that I will NEVER send), it can be good to get it out of your head and onto paper. Also, if you look back at them further down the line you'll see how far you've come and probably not even recognise who you are today.
Don't be in such a rush to move on that you ignore tidying up the remnants of dicky's treatment of you. Your therapy should help, hopefully your therapist will have a good understanding of abuse and the damage it can cause. Also look up Dr Ramani on YouTube.
And in between do little things that bring you pleasure - go out and collect pretty leaves, take photos of the autumn colours, sunlight and stormy skies, re-arrange the cushions, a nice treat for your evening meal.