She went insane and started thinking that everyone was trying to kill her.她疯了，开始以为每个人都想杀她。

I must be going insane. I can't find my car keys anywhere.我快疯了，哪里也找不到我的汽车钥匙。

If you don't stop making that noise, I'm going to go (completely) insane!如果你不停止制造噪声，我就要（彻底）疯掉了。