What the the generic requirements needed for a patient to officially no longer need antipsychotics?

My first time in the hospital, I was in the children's ward and my psychiatrist said that if I could go a year without another hospitalization, then he would slowly wean me off my medication and I'd be good.

I ended up having three more hospitalizations after that and now my psychiatrist is saying I'll be on my medication indefinitely.

But, if I do really well and I tell him all the voices I'm hearing, or all the thoughts I'm having and they stay under control, can I eventually come off my medication?

My medication is currently costing me over $1000 a month and I really can't afford it anymore. But I don't want to switch medications because I have a hard time switching and it always lands me in the hospital each time I mess around with my meds. I'm sick of the meds now and I want to come off them.

I'm 20 years old now and I've been on medication for years and I feel like I'm ready to come off. I've gone a whole year now without having to go to the hospital and I've had my medication reduced a few times and I'm feeling pretty good. I don't plan on being medicated my whole life.

So, back to my question at hand, are there any general rules or requirements that tell a psychiatrist that their patient is ready to come off their meds?