I am sorry you are having to endure such a severe depression.
I know it feels like its never going to end.

It's very painful!
I mean this with respect for all you are enduring: You depressions have eventually lifted before and it will again. The question is when? It's tough not knowing that answer. BP is cyclical and you will cycle out of depression.
How to endure it in the meantime?
An incredible amount of patience.
I've been going through this, too. I get to where I think it will never end. I find I can endure only by letting my rational mind have the last word. The emotional part of my mind is convinced there's no end to the depression and my efforts are futile.
Sometimes nobody can say anything helpful to me, even though they are trying.
You are in a very tough spot, dear lady.

I hope you will find the patience to get through it.
I wish I could be more helpful.

WC