LLM's are surprisingly good at giving advice about minor personal problems and social situations, probably on par with a newspaper advice columnist. It's not therapy but that doesn't mean it's not useful. The main problem is it's relentlessly positive and it's not going to give you 'tough love' advice, so if you're really a mess you're not going to hear what you need to hear.
I think I can't trust a therapist enough to be completely honest, while I can just write anything into the chat, knowing no one, (except google) will ever know :D
