I totally can feel your pain. My bipolar meds messed me up and put me up to 192 pounds. And I'm only 5'4". I eventually lost it and became anorexic. I'm now in recovery and I feel gross. I'm not fat, but I think I am.
I know how comforting it feels to eat, how depression about how we look just makes the depression worse. That's when I sought help with a therapist. Is there someone you can talk to, like a therapist? Mine helped alot.
I know it's scary to want to lose weight and fear how far you can take it. I'd like to shed a few pounds, but I constantly have my husband at my side asking me what I ate and pretty much making me eat. He's a great support system, even though I wish he'd "unsupport" me for a little while.
Maybe there's a sweet tasting fruit you could replace your chocolate with?
Hope you feel better.