Don't fix it; move on
If you have a troubled relationship with a client, the best thing you can do is find a new project where you don't work with that client.
Trying to fix it is almost certainly not worth it because clients have the upper hand in the power dynamic (unless you changed all the passwords to key programs, in which case you might have leverage...).
If you try to fix it, you're just going to be frustrated.
Use that energy to find a gig that's a better fit.
Want the full playbook? Check out Going 1099.