It doesn't pass on the pain.
The pain and suffering of a suicidal person is a different feeling to the pain felt when you lose someone.
I've just come through a severe episode. I still reckon one day I won't.
Several friends of mine have committed suicide over the years. And I've lost several friends and family to illnesses and old age, a combination of knowing someone will die, and surprises.
I've seen people affected by the suicide of friends and family for years, but there's many of us who can get through it because we understand because it's a place we visit.
Last funeral for a friend who commited suicide was this summer, this year. The sibling who I was close to growing up, said that it was both the worst pain felt plus a relief because they'd been mentally ill for so many years it was sort of expected to happen sometime despite all they did as a family to help.
There are times I don't understand why someone does it, when someone kills their family or the kids then themselves. That's something I've not felt the need or desire to ever do, and I don't see it quite the same.
Think of your 'regular' suicide. Say, a person who has felt ill for years, may or may not show it often, but people know about it. That person will have been guilted at least by the sorts of comments by people on this thread, if not some people in person, including friends or family.
They still complete suicide. But a huge part of what's eaten them up is the feeling that what they're experiencing is so wrong on the behalf of other people who aren't the ones experiencing their own personal pain.
I nearly didn't come through this episode. And that's a very personal thing. Not even my partner can or will ever understand it as it is for me. Yes it sounds selfish for some people. I can't change what people think. I'll always try and help friends where I can, if they'll let me. But I've learnt to let go if someone else cannot hold on anymore.
It's not right. But calling it selfish in every single instance just makes people who feel that way, feel 100% worse.