Love of my Life

I’ve been dating the same dude for almost a year. He is amazing and I couldn’t even think about leaving him. He has messed up in the past but I forgave him and we moved on. The issue is, he hasn’t forgiven himself. Now sometimes he says he loves me and we make elaborate plans to move forward to the next steps of or lives. The next day he says he doesn’t and he can only feel hatred not towards me but towards the world. I know later he will love me again and I just end up waiting. It hurts because I know he still loves me. He admitted he always loves me but sometimes he gets so mad at the world and it takes up his emotions. I’ll never leave him and I do give him space, but it’s been happening for months and I don’t know what to do.my goal is to wait this out and be there for him always and I will continue to do so until someone gives some advice that isn’t “leave him”. ( I know it’s stupid but that isn’t an option).