You can be good friends with someone without having the sort of connection that makes discussing some specific issue possible. That doesn’t mean the connection isn’t genuine, even if the scope of it is not as broad as you wish it was. Regarding venting in particular: in my experience, it’s fairly common that people don’t want to listen to heavy stuff that they can’t help you fix. I often have things that makes me sad which I want to put into words even though they can’t be fixed, and I find that for that sort of thing AI can actually be a good “listener” of a sort.