[Itse]

In the case of pretty much all the the addicts I've met, the addiction is the result of a constant need to self-medicate their problems away. Depression, anxiety, even phobias can turn people to look for relief in alcohol or drugs. Simple poverty can be a reason for people to take drugs. (Or I guess the anxiety and hopelessness caused by poverty.)

When people feel like they can't take their lives for another day, they will either kill themselves or find something to take the pain away. Most get drunk because it's legal. Some take harder stuff. When things are bad enough, stuff like fentanyl or krokodil become a win-win scenario. Either you die or you get high, either way you won't feel the pain anymore.

This is BTW one big reason why I really hate it that there's so much shame and fear around taking prescription medication for your mental problems. They're not perfect, but they're very often much better than the solutions people find on their own.