Agreeing with fairnymph, it's pretty clear opioids just provide symptomatic relief -- you were depressed, they get you really high, so of course you're happy! When the high wears off, you're just as depressed as before... maybe worse cause you wanna be high again. (I know the feeling)
Now maybe this would be fine, if you could just stay high all the time and that would work. However that's impossible for the vast majority of people, the way things are now.
Antidepressants at least strike closer to the source, not just masking the depression with euphoric mood lift. Now whether they "fix" the problem I don't know -- sometimes they seem to, as they can be discontinued without remission. Many people though must remain on them or relapse.
Another point is that using opioids for depression is a fucking open door for all sorts of other problems, namely addiction. This is a point I want to belabor:
Psychological drug addiction is an objective, factual condition. It's not just a case of weak will, or similar to liking women, or shopping, etc. It's a particular, definite biological process! There is a distinct "reward button" in our brains, located around something called the
nucleus accumbens. With most things we like -- sex, money, food, etc -- our brain does filtering, so they don't press this button too much. After you've had say a lot of sex, it doesn't press this button so much: it might still feel great, but your "craving" for sex doesn't increase. (except in nymphomaniacs). You can use brainscans and
see directly that normal activities quickly lose their ability to press this reward button.
Addictive drugs though pretty much bypass the brain's filtering mechanism. They hit the reward button directly, in a way the brain was never prepared for. One of the main things the reward button does is inciting
learning -- making sure you learn the right behaviors to get those rewards! With drugs that keep pushing the button, people overlearn, and it turns into an obsession with the drug
and things associated with it. I'm sure most of you have noticed the weird obsession with drug rituals and paraphernalia that addicted people tend to have.
Now I like drugs too, but I think it's important to understand that addiction isn't just a little thing of losing willpower etc. It's this particular biological process. Now sure, those with "stronger wills" can resist addiction longer, and individual psychology plays a big role. But it's also somewhat random. For example, some people have genes that make alcohol press the reward button stronger than others; and these people are much more likely to become alcoholics than normal, even if they have a strong will.
This has wandered somewhat offtopic... my apologies.
