Are alcohol and light drugs really helping or just covering the problem?

Keep in mind that a psychiatric hospital is working on actual psychiatric disorders, i.e. super serious medical problems (where your brain is rewired in "interesting" new ways, possibly forever). We're not discussing about a psychologist here, who's working on what are comparatively mild conditions.

Doesn’t help with a broken leg either.

My friends who are addicts (those that have survived) are using serious drugs and most of them have complex issues to deal with.

But lighter drugs, whether analgesics or pot/alcohol aren’t of any use for serious illness. And those kinds of drugs are the ones under discussion.

Cope.