She refuses to enroll into mediation or counseling. Must I involve the Court?

I didn't phrase part of my story correctly. She won't work and I have stopped asking for rent. She has never paid rent.

Eviction is a legal process. You can tell your daughter to leave, but if she refuses, you have to go to court.

You have to give her legal notice (which varies by area) to vacate in writing. If the deadline to leave passes, then you have to go to court for an eviction order.

Agree, you an evict, even if she is not paying rent. You will give her notice, and if she does not move out, you go to court to evict