Is there a way to encourage someone to get help without being patronising?

I am going to school for counseling and social work, so I am biased towards therapy obviously, I encourage it.

PTSD- you have little chance of succesfully dealing with it without therapy. You really need some form of it.

I won’t get into crazy detail, not really my story to tell. But my dad was also there that night, he stayed with my mom while the EMTs were working on her… So yeah. He has PTSD. I know, armchair psychologist here. However, the things he has told me… literally a random person on the street would go “Yeah, that’s PTSD”

He gets very mad at the idea of therapy, he thinks he has it all figured out. Any attempt at talking to him starts a MAJOR argument.

I have never gotten along with him, but he is my dad. I was going to let it go until he said he thinks it should have been him. Now I am worried.

I brought up my own flashbacks and tried asking him, he got mad.

If it seems like too much of a losing battle, I will back off. However, I still want to try, somehow. I know how much I am struggling, he has never been with anyone else other than her. For almost 30 years. Ignoring all the negatives of that relationship it was very, very toxic he still has that relationship. So as much as I am hurting, cannot imagine his side.

I want him to get help.