@Movingon83, I can totally relate to what you are going through. That constant feeling of being on high alert for the next attack. The frustration of not seeing an end to it.
I was recently put through a two year court case by my narcissistic, emotionally abusive ex-husband. He used the scorched earth method - refused any form of reasonable agreement, lied, hid assets, played mind games, involved third parties, anything to cause as much emotional and financial damage as he could because he knew he was going to lose. He didn't get anywhere near what he wanted and I ended up with a clean break for which I thank my lucky starts every day.
Not sure if this will help you but how did I survive?
On a practical level:
Took over the legal work to avoid the hefty legal fees - represented myself at hearings to get disclosure and FDR. I reckon I read enough to qualify as a solicitor but I felt in control which really helped. I am sure you are capable of representing yourself.
Took advice of a direct access barrister instead of a solicitor - gave me an idea of what to expect in court which I followed. Kept my side of things reasonable and flexible with a view to not being tied to him anymore, even if that meant losing all I was entitled to.
Did not react at all to his ranty emails and manipulative communications - if I thought a communication was likely to upset me, I got someone to screen it first. I only communicated when I had to and kept it brief, to the point and emotionless.
I am not sure judges recognise emotional abuse but I had a male judge who saw straight through his manipulations. It was priceless!
Try to get a clean break if you can Op. Being tied to this type of person will not do your mental health any good going forward. Mine started out as Disney dad to our child, got a new woman and then lost interest so that tie disappeared. Best option for both of us.
On an emotional level:
Used a very good therapist to talk about my feelings, mostly my fears and frustrations.
Talked about the case to a couple of very good friends but not so much that I wore them out
Went to yoga regularly to de stress
Did loads of jigsaw puzzles, colouring books - anything that you have to concentrate on
Walked my dogs in the fresh air every day - nature is very therapeutic
Screamed and cursed about the awful person I used to be married to at the top of my voice in my car (must have looked like a nutter but really helped relieve some of the stress - therapist suggested this)
Did stuff that I enjoyed, that engaged me - took some classes, writing, painting, journaling
It was the most awful, stressful, upsetting and frightening time but I feel very proud that I stood my ground. As another poster said you may regret giving up and he is probably counting on grinding you down to get more than his share.
Good luck . Look at this as a very small part of a big life free from this pile of mental clutter that you married.