How can I help my friend overcome active suicidal thoughts after he was cheated on?

I (28M) am going through quite a difficult period of my life. About a month ago my closest friend (28M) shared with me that his girlfriend (28F), who is also my friend, had been cheating on him for months with her female coworker. The affair did not involve sex, but it was romantic nonetheless.

He expressed his readiness to forgive it (they have been together for almost seven years and he loves her very much), but she still hesitates if she wants it and considers leaving him to pursue her new relationship. It’s been almost a month since the affair was uncovered, but she still hasn’t made up her mind.

A few moments ago he shared with me that he attempted suicide, but he stepped back last minute. He promised me not to hurt himself, at least in the observable future.

I suggested help with finding a psychiatrist, but he dismissed it. I also offered spending more time together, but I am afraid I cannot be there for him as much as I would like to because my wife is pregnant and I am starting a new job.

What can be done in this situation? I desperately need an advice