go out of (one's) mind
1. To become wild, irrational, senseless, or insane. She went out of her mind at the sight of her child lying lifeless on the cot. All this noise in the house, day in, day out—I feel like I'm going out of my mind!
2. To become extremely excited or enthusiastic (about something). I've never understood that pop star's popularity, but kids just go out of their minds for her music.