Some advice?

I feel empty and lonely. I became attached to someone I was in a relationship with before we broke up. We talked as friends, and things started to improve, even though months passed and I was trying to get back together. Then, two days ago, he suddenly decided not to forgive me. He said he refuses to try and that I have to choose between us breaking up completely or continuing to talk as strangers, less than friends. I'm lost now. I don't know what to do. I'm scared and hesitant, and I want to free myself from my attachment and feelings for him. I've also been diagnosed with severe depression, and my brain doesn't produce the happiness hormone like a normal person, so I experience frequent bouts of sadness. My medication is for psychosis I might have it or bipolar disorder, but they don't want to tell me.