Stay strong - you CAN do this. I was where you are just over 12 months ago. I also read Lundy Bancroft while we were still together, and 'observed' his behaviour and journaled it all, before asking him to leave. He'd always made me believe I was mad, mental, crazy and imagining things, so the journal really helped as I KNEW he'd said and done the things I alleged. Sure enough, he practically followed the script word for word.
We are now divorced - he spent a fortune in a solicitor, I had 2 hours of paid for advice and did the rest myself. Not boasting at all, but I just plodded through it, telling the truth. I didn't do mediation, as I knew he'd bully me in to submission. We went to court and I received 100% of the equity in the marital home and a decent sum of maintenance per month for two children. This resulted in him moaning at his solicitor for being useless!!!
The children live with me 11 out of 14 days, despite him threatening the "you're an unfit mother, you won't cope, I'll get custody blah, blah, blah".
Anyhow, I've just sold the house, and am using the equity to purchase a lease on a shop (I'm a florist) 200 miles away, am renting a lovely house for me and the children and moving on to A BRAND NEW LIFE. I didn't work before, he didn't want me to and was isolated from family and friends. He used to tell me "people don't like you, you're this, that and the other" which I believed, so it's been amazing to find people actually DO like me.
You'll be surprised at what you have the strength and ability to do - all the negative things he put in your head will disappear.
YOU CAN ALSO DO THIS (or what it is YOU want to do with YOUR life). You will MORE than cope without him and no matter how many times he cries that he'll change HE WON'T. No matter what you do to try and make him change IT WON'T WORK.
Please - you've actually done the hardest part, which is accepting that they're abusive and getting rid. The rest won't always be easy, but you'll have your sanity, and that's priceless. Life is so short, please move forwards without him because you CAN DO IT and will be so much happier.
Wishing you every blessing, stay strong - you're right - it is like grieving, because we grieve for what we THOUGHT we had, and what we thought we were giving our children. The reality of life with an abuser is crap though, they keep us hooked with the nice stuff and make us feel it's our fault they're nasty. The nice stuff is worth nothing in the end though, because we pay for it with our sanity and health.
You will find lasting happiness without him.