Hi, welcome to the forums.
My heart goes out to you and this situation. It is obviously painful for you to witness the man you love going through this mental torture.
i am not the person that can tell you which angels etc to ask, I have however been in this man's position and went to some very dark places mentally and physically. I have also bee in your position too, that of caring for someone who seems almost lost to us (in the pyschological/mental health sense)
I feel you need to be concentrating on looking after yourself, ask the angels for guidance for you, pray or whatever you need to do to stay spiritually healthy (Kuan Yin is who I turned to in my darker hours).
As far as your partner's situation, unless he is open to angel healing and crystals etc, I do not feel it is gong to benefit to him.
Ultimately he needs professional help if he is spiraling into deep depression, and helping him get this is probably the best thing you can do for him right now. Then you need to make yourself strong again.
I'm sorry it may not be the answer you were looking for but I hope it helps.