jbug, I hope you will not go off of your meds for a week just to prove you need them. Even if you don't need some of them, going cold turkey could throw you for a loop. Psychoactive meds should be tailed off gradually.

Would it help if your pdoc wrote an official evaluation of your need for meds, signed it, and gave it to you? Then you could share this with your father to demonstrate your need?

Is there any way you can become more financially independent of your father--write your own checks, not need to ask for gas money, etc.? It sounds like you live independently and have a job--are you able to manage your own money? If not, is there any way you could put someone in charge of it who is not so hostile and toxic? Would your mom be better? It is terrible how your father is using his financial authority to ransom your car and blackmail you. That must feel so disempowering. Do you have a social worker who could intervene to help find a solution? Would family therapy help? Just throwing out ideas....

Hang in there, jbug.