Perhaps you can state, "My brain illness is acting up today."

I think it may be coz he feels so useless himself due to depression.I know this happened with me

I went thru the same thing. Only my husband does not suffer from any mental illness. He would get so angry because I tend to isolate myself from everyone. Finally one day I sat him down and told him everything depression and anxiety and PTSD did to me. I mean in detail. The darkness the feeling of being useless and lazy. Everything I was going thru. Then I explained it had absolutely nothing to do with him. It was me my illness was causing me to go inside myself because I felt damaged and ashamed and so many other things. That it was all I could do to just get myself thru the day. And in the end I had nothing left to give to anyone else. But I also told him I was doing everything I could with my dr.to get better. This was only temporary and just to hold on and just b patient. Most people dont understand the depths depression will take on. If people cant see it than it doesn't really exist to them. Make him listen and dont hold back and hopefully hell begin to understand what your really going thru. Most importantly make sure he knows it's not him and there is nothing he can do to fix it. Hope this helped. B strong

say maybe uhm this isn't about u honey it's about me

On the other foot
It's hard we are thr ones at fault.