Hey there @Chosen1 good on you for noticing the "sinking ship" situation and getting yourself and the kids out of there. Literally this is "the beginning of the rest of your life" with the continuation of your old one, and the loss of your old life too, merging into something new and different that may not be clear to see at this point. Are you getting the situation where you finally have a break from the old situation so your brain/body is throwing up all the memories? That can definitely happen.
I agree that healing and recovery is hard if not harder than riding along on the sinking ship. "those people" live in a storm of chaos and problems, those of us close to them catch the problems and attitudes then need to solve problems and rebalance perspective after being around a strong influence or controlling person.
Have you got a dream board going on? Something that just helps you literally see and remember 'the dream life' you were hoping for. For a long time in my own life, I was hoping just to "not do certain things and do other certain things" which involved throwing away addiction and self destruction to "become stable and normal". Like filling a hole or panel beating a car, it was boring, frustrating and very difficult to get through that first phase of "undoing damage and learning better life skills".
From there I could "add stuff into life that's actually positive, not just undoing negative"...to try to depict it:
(messed up life)<-----(repairing damage)----->||NORMAL/STABLE||<-------(adding better stuff in and seeing what works)---------->(better life)
After 15 years of serious recovery thats how I have come to see it. I recall it was very scary to recognise all the damage done by others and self inflicted, then to address that, then to grow from there. But, I look back on my life in wonder now and I think, wow it took a lot of effort to build a dam to stop self destruction, but once I did that it was pretty self-perpetuating to get the rebuilding phase together.
Do you have good physical and emotional supports? Are you in touch with counselling type relationship who can help you with the hard stuff and push you towards the better stuff? Have you taken stock of what you "lost" and what you need to get back? Self respect, self esteem, peace of mind etc.
Be careful you may find yourself VERY angry at the abuser/non-responsibility-taker and you might find when they're gone you are stuck with a lot of anger/sadness that is hard to shift. It is very important to get this anger and grief out of your system, it's your body screaming out what was wrong all that time and it NEEDS to come out by expression, movement, fully feeling the emotions/pain and resolving those into strength and meaning.
All the best, yourself and hopefully your three kids will thank you for making the effort. My Mum didn't leave my dad til it was too late, and I feel sad for her she lost so many years. In order to keep her dominance over my brothers, she didn't resolve the bad behaviour and disrespect that keeps them enmeshed in abusive relationships with men. She is now in her mid 60s and still having daily fights with her own children which give her a sense of power and control. But she is desperately unhappy in her interior.
What I am trying to say there is dont compromise and don't lower your goals and standards after you have gone through this pain it's a brand new chapter ahead to truly write the next chapter of life, and make all the sacrifice worth it by setting yourself up for a much better future WITHOUT the nasty things that dragged you back the first time, and I don't want to be a downer but sometimes the kids choose the easy way that was demonstrated by the less responsible parent. I did that for some time and then I realised that I wanted to rewrite life from the ground up which was doing everything the hard way but also never going back down a rabbithole of opening myself up to familiar pains and frustrating circumstances which came from staying in the familiar chaos and no wonder I had familiar problems in my life.
Last but not least congratulations and good luck, in this time suck up every resource that helps you move forward, reconcile the facts of the past, and things that let you cling on to hope for the future too.