Why do you self-medicate? Or not?

I’ve heard that people self-medicate to hide a pain. I know a number of bipolar folks who have self-medicated to combat depression. Usually pot and alcohol. Ironic, because alcohol is a depressant.

I think folks who have experienced horrendous things, self-medicate to keep from remembering those things, or to keep the bad dreams away. I don’t know how well this works.

What I’m wondering is, for anyone willing to say, what horrors have you experienced that you use alcohol or illegal drugs to keep at bay?

For those who have not turned to self-medication in order to deal with the horrible parts of your life, how come you haven’t?