I would and have posted about truly awful things happening to me. I haven't got any rl support, so online support is invaluable. It's the only way I've made it through the last few years.
And I am not a troll. I no longer tell my whole story on one thread anymore, as it's something that at best, people find hard to relate to, and at worse some people enjoy digging in and causing unnecessary hurt for their own motivations.
It's a sad truth that for some people, it's more comfortable to believe people's lives don't really fall apart in the way mine did. It's easier to believe someone's telling lies than that life really is that random. It's also more of a comfort for others to try and find what I did wrong to cause fate to dump this shite on me. I've had people in rl asking all sorts of (intrusive and rude) questions to try and prove their assumption that somehow everyone is completely in control of their destiny and therefore they are immune to the bad things in life. They get very uncomfortable if I answer their questions and they still can't find a way to put distance between them and their clever choices, and me and my err, oh, shot just happens even if you're prepared. If something bad happens, it must be avoidable for 'people like them' and their has to be a story of blame somewhere.
It's one of the unexpected kickers that accompany real tragedy. Alot of people edge away pretty damn quick.
I hope other people don't put their troll radar so as to disbelieve anyone who is having a really hard time, and going through real tragedy.
I hope the bar is set higher than that. It's not so much about 'no one would post rl serious issues' and perhaps more about taking a moment to think 'how, when and where' would this poster be posting during a serious rl issue as its unfolding. And how neat the story is.
Real life is messy and complicated, and people tend to stop posting whilst something is unfolding, then post later that day/ evening. Or post when they most need support, or at times when they can fall apart a bit. Real life tends to be pretty unrelenting even when something bad is happening, so rl tends to intrude on posting ability, and not be around to focus on the pace and reveal of a situation.
I've only ever got caught by one troll and in that case I got a flood of PMs explaining what was going on, and that it was a previously banned poster.