Opinions please!?!?!?

So my step dad has depression (been in my life since I was3) and it is taking a huge toll on my family and I!

He moved in with us because he can’t hold a job down and blows his money on stuff he don’t need!

We have managed to have him hold a steady job and he still has other stuff to work on but it’s getting there.

When his depression acts up he goes completely silent (he use to be violent) refuses to talk to us and has even shut himself in his room away from us and my 2 year old who is trying hard to play with him!

Then he will call my mother (his ex wife) and talk crap about my family and I!

We pay all the bills, he doesn’t clean, and he is always saying we take advantage of him.

We want him to get help and see a doctor. He refuses and tells us that doctors don’t care and it builds up to the point where he starts blaming the government for all his problems.

If he does see a doctor, and get meds, we are worried he won’t take them.

He has threatened his life before and attempted (many years ago)!

I just don’t know what to do....?