It sounds to me as though you probably did more than could be expected. Many marriages end with far less effort invested toward saving them. Some of us who struggle with mental illness are able to maintain at some reasonable level. But others just continue to go downhill no matter what. There's simply nothing we can grab hold of to stop the descent. Sometimes we experience both to varying degrees.

I'm married to a wonderful woman who I feel is very much like you in terms of her devotion. But I'm constantly aware that she must have her limit too. So I struggle daily to try to do what my mental illness demands of me while not stressing our relationship any farther than necessary. I'm constantly second-guessing myself. And I'll admit it is wearing. Sometimes... no... frequently, I find myself wishing I could just let go & give myself over entirely to my illness. So far, I can't. But that doesn't mean it won't happen at some point. If that happens I'm certain my wife will ask the same questions you are asking.

I do hope that you have someone in real life you can talk all of this out with: either a close friend or a therapist. It will take time to resolve all of the conflicts in your heart.