Well... I'd have to admit that, to me, getting high isn't really an answer for anything in the long run. Especially if one has mental health issues, it seems to me it's like throwing gasoline on burning embers. That said, if you're having a mental breakdown, perhaps the thing to do is to get with the mental health providers in your life (therapist, psychologist, psychiatrist) & discuss with them what the best plan of action might be. (And if you don't have any mental health providers working with you at this point, perhaps the time is nigh?)

Beyond that, for more everyday mental health concerns such as negative emotions, difficult thoughts & / or memories, my go-to practice is something that is referred to as compassionate abiding. Here's a link to a description of the practice:

Relieve Distress By Allowing It: Compassionate Abiding 101 | Mindset: Perspective Is Everything

There certainly are lots of things a person can do day-to-day to help themselves out with everyday mental health issues. But if a person is having a real mental breakdown, it seems to me that calls for bringing in the professionals. I wish you well...