My sister uses drugs, she has been to treatment numerous times, shes been in therapy every week for four years. but she still uses daily. i know she wants to get sober nobody wants to be an addict. what should she do?

Besides committing to different therapeutic programs (individual and group counseling in addition to pharmaceutical therapy), she should move out of her current environment which makes drug access is much harder and she can escape the routine interaction.

This is one of the most complicated medical condition to treat as the medical system has limited ways of dealing with such patients, who need significant changes in their lifestyle and continuous support for years in order to avoid relapses. A long term facility far from current location and entourage with proper motivational and psychological long term support will be needed.

Take her to a hospital to see patients being treated for drug overdoses, and if that doesn't work than a morgue to see the end result. Maybe that will shock her into reality.