I am sorry you feel the thread has attracted nastiness, but every so often someone is going to express an opinion to the question AIBU? And if their opinion is at all questioning they are immediately accused of nastiness, troublemaking, not understanding (how does anybody know?) and told not to post on "your" thread. There have been several replies to posts in this vein from the same 3or 4 people, and no, I will not name names.
I do understand that you as a group derive comfort from your conversations, but why not put it under "grandparenting" or "Relationships" and make it clear it is a sort of support line.
Just because the thread started on AIBU doesn't mean it is set in stone - and perhaps some heartache will be avoided.
Before anybody jumps down my throat again accept this is kindly meant.