Fiancé backing out 2 months before wedding? :(

Ladies, I need to vent. I feel like I have no one to talk to. If so, I feel like I’ll be judged and ridiculed. Basically, I’m 2 months away from my wedding. My fiancé of 2 years texts me and tells me he feels useless and just “doesn’t know” .. he’s being very hard headed to talk to, and confessed to me, he’s been diagnosed with severe chronic depression during the army, but now 3 years later he’s been off medications and mentally fighting it. I NEVER knew he was clinically diagnosed until last week. We never lived together and saw each other twice a week, because I was a full time student and worked, as so did he. We moved together this recent march & I didn’t see any changes. I feel so stupid though and heartbroken I didn’t notice sooner. 😔

we talked, the other day and now he says he does want to marry me, and he avoids talking about anything else. I don’t know what to do. Any words of advice would be nice. I’ve been sick to my stomach and scared to even walk down the aisle 😔😔💔