Hi Joan, I found myself in a similar situation, and it really gutted me. I have a housing officer who helps me with financial issues that arose in my last serious mania, and who has helped me with benefits, supported me with disability interviews etc. She's also a mental health nurse, and has written me letters to support the British equivalent of disabilty payements... she's said that I have a "serious and enduring mental health issue."
Well, schizoaffective (or bipolar) is a serious issue, and while it's not necessarily going to be permanent, there is a permanent risk that the disease might return... in which case her statement ( serious and enduring) is accurate. I think this is what your doctor is doing. I really do understand how horrible it is hearing the diagnoses (I had it multiple times... the last two being bipolar and schizoaffective. Just don't worry about how the label makes you feel... what it actually does is inform other medical professionals whereabout you stand on a spectrum. Your doctor is looking out for your interests... and yes, you can get better despite that judgement.

DON'T WORRY!

You'll be fine.

(((hug)))