Zetlander -
I was deeply moved reading what you had to relate.
I have myself suffered with mental health issues, and I know how devastating they can be.
I suspect that you and your siblings have wondered, and worried at times, whether your mother's mental health issues were due to some heritable trait and if so whether you might have inherited it and were at risk of mental health breakdowns yourselves. And I suspect that you felt immense relief (along, no doubt, with terrible sadness) on discovering this story. The relief was due to the realisation that there was a discrete and probable cause for your mother's breakdown. A one-off external event, rather than something that you were in danger of inheriting.
If I am right in that suspicion, then I think you must share this with your siblings. They may never had spoken of having such fears. But I am sure they must have harboured them. And they will welcome the relief of finding that there is an alternative explanation (terrible though it may be).
Aunts, uncles, cousins?
That one is more difficult. But I think there is still a clear case for supposing that they may have concerns about the prospect of there being "mental illness in the family". Again, they may not have spoken of it, but it is probably there. Certainly if any of them have shown signs of being worried by this, then I woul dbe inclined to offer them the reassurance.
More remote relatives?
No, I think not. Anyone more remote than uncles, aunts and first cousins can, at the closest, be siblings or descendants of siblings, of your grandfather. Doesn't affect them. The siblings will have decided what they wanted to tell to their children and that will be the story that is passed down in those families. Anyone there interested in researching it will find that it is not true. But let them discover it for themselves if interested, or not if they ar euninterested. Nobody is harmed either way.
