When my best friend ctb, I would say firstly virtually everyone was shocked and confused. Only his mother and I knew about his previous attempt and that this was a significant possibility. Circumstantially it didn't add up - he had money, a job, a house, a wife and kids, physical health was fine, etc. So at the funeral, people talked about how you never know what the person next to you is going through inside and similar mental health related things.
Secondly, about the method itself (he jumped in front of a truck), the general feel was anger that he would do that to another person. A theme that comes up a lot here is how difficult it is to actually ctb. That's not a theme I think the general public is aware of. They view jumping in front of a truck as incredibly selfish and the idea there was no other way isn't something that comes up.
For me, he had told me about his previous attempt (car exhaust method), that he was disappointed he was found by his mother before he died, and that he would likely try again. That he was basically suicidal his whole life and nothing had changed. We had maybe 12 hours one night discussing it at great length. At that point, I had seen him most days of his entire life for 30 odd years. I knew him better than anyone. And this was all basically new to me. I knew he had a level of self-hatred that was extreme and non-sensical. I guess before that I always viewed it as like an extreme form of humility. But for him it was more like a deep disgust. His body, his mind, his life, everything about him was so abhorrent to him he couldn't stand it. He was the worst and everyone else was better. This came out in outbursts of self-directed anger somewhat frequently, especially when he lost a game or did anything remotely inaccurately, which was the only real outward sign people had that something was amiss. But he'd done that his whole life, since he was a little kid, so it largely got dismissed. He was confused how I didn't know, or almost everyone didn't know, and brought up how I had watched him bang his head against a wall repeatedly until it bled on multiple occasions. It's interesting how that gets re-contextualised. I didn't understand reactions that extreme, but I didn't link it to potential suicide. I asked about the circumstantial things - money, family, physical health - but there were no significant issues with them, he just viewed it as irrelevant comparatively. He can't stand himself, so what use are those things?
We never spoke about those things again after that night. And many years went by before he ctb. So I guess I thought he might have changed. But nothing changed. At the funeral his mother said he had mentioned a suicide forum to her, which is how I found this site. Looking firstly for his posts (which I never found and am now confident don't exist) and then to try to understand him through others in a similar position. But I must admit, having been here for 5 years, I haven't seen someone here that's very similar to him. Everyone is different in their own way.
I'm still here, over 5 years on. I still think about him, and his suicide, most days. I still don't understand.
