We do not ban discussions of suicide on our site, since, after all, we are a mental health support site. It would be pretty rare for someone who's gone through clinical depression to not have experienced such thoughts at least once...
We do have a policy about discussion of suicide and topics in this area:
https://forums.psychcentral.com/depr...resources.html
We just ask that people properly trigger their posts as such, and refrain from posting about any detailed plans, methods, or such.
I'd encourage members not to focus on the specific issue ("Are they talking about suicide?!") so much as what they're actually trying to communicate -- reaching out for help and for someone to just listen to them and hear them...
Best,
DocJohn