Betrayed

My best friend/roommate who is a recovering heroin addict just stole sleeping pills from me for what she claims was the first time and lied about it to my face multiple times in a row. We talked and she agreed to get help otherwise she will be kicked out.
Yet I feel as though I am being foolish and dooped. And I cannot get over the incredible urge to hit her. I don't know what to do. I love her, she's my best friend, but I just want to fucking hit her and kick her to the curb whether she has any place to go or not. I don't know what to do.