Husband having suicidal thoughts

I just got off the phone with my husband. I don’t know where else to ask for advice for this and I apologize for the long post. He was on lunch break at work - I’m on maternity leave with our two month old son. We also have an three year old daughter. I had a high risk pregnancy with complications and I was in and out of the hospital the last few months. Our son was born with a heart arrhythmia so things have been stressful.

He told me the past 2-3 weeks he’s been having suicidal thoughts almost every day. And for hours a day. Like that’s a lot. He’s had a history of suicidal thoughts his whole life so I’m not totally blindsided by that but usually much less frequently. However, ever since I convinced to start taking anti-depression pills he says those thoughts are getting a lot worse.

I don’t know what to do or how to help or support him. I recommend therapy because he had a traumatic childhood but he always shoots it down and now gets mad when I mention it. He had to go to go the psych ward back in high school and feels they just try and shove pills at him. I wish he would just try though.

Obviously his feelings and thoughts are not something I understand, so I don’t know how to handle it. Anyone have any advice? It hurts me to hear too, thinking that me and our kids aren’t enough for him, he’s not happy with his life with us, etc. I realize those are selfish thoughts but it’s hard not to have them. He promised me he wouldn’t do anything but said he was getting worried about how often he’s having them. How do I help him? Any thoughts on how I could convince him to try therapy too?