I have been researching making a therapy chat bot for years... it's going to happen. https://github.com/andrewt3000/carl_voice
To be honest, the thought of AI doing therapy (and it's reliance on big data) sounds very black mirror to me. How long do you think it'll take ad companies to do an end run around patient protections and start serving ads based on "metadata"? Got anxiety? Try our new meds! Worried about the future? How about some life insurance or annuities? Etc. Things will get very exploitative very fast.
Learned about it in the documentary Century of the Self, an outstanding work.