JMO, but I think you should tell your T about the cutting and the drinking. What kind of trouble could you get into? Are you worried about being hospitalized against your will?

The more honest you are with your T the more he can help you.

And if you don't want to go to the hospital, make a safety contract with your T.

I'm concerned about you. How are you doing today?
Take Care and let others help you do that. (like your T)