For your own sake, fill your mind with new things, good things, enjoyable things. What price your own health?
You have had a battering with these people, I would be careful about going back for more. Even if you win the money you do not want to put yourself up as a punch ball. And you will come under scrutiny and things will be twisted.
I have a friend who was constructively dismissed and it seemed fairly obvious but she was up against a council and their employment solicitors. Even having worked in the legal profession, she had to call it a day as her health deteriorated under the stress.
Look at what is right in your life, a lovely husband and son; other contracts which go smoothly; your own achievements in getting your doctorate; overcoming prescription drug addiction. These are no mean achievements, and bode well for the future.
Life is not fair, but rarely rectified by going back to past injustices. It just robs you of more time and mental anguish.
I was helped a lot by some books, one started me off on a new thought pattern. It's an old book and from a Christian perspective, 'The power of positive thinking' by Norman Vincent Peale. Happy to lend you it if you want.