(to be clear, I'm no more qualified than you, probably less, I'm just a computer technician speculating about how the brain works;)
I always felt like trying to fit my feelings into a logical model that had to do with other feelings was a losing game. As far as I can tell, how healthy I am in other ways matters more to my feelings than anything else; when I'm doing badly, little bad things seem huge; when I'm depressed, it feels like I've always been depressed. When I'm doing well? the opposite is true. Feelings just... they aren't logic. they don't seem to operate under the rules of logic.
I guess I think of bad feelings like any other kind of difficult to pinpoint bodily pain... something is wrong with me, but the thing that is wrong is often not the thing that hurts.
I personally think there's way too much stigma associated with drugs; I mean, for me, fitness levels have a lot to do with mood, and goddamn, it's hard to get myself to work out when I'm depressed, so I can get in this sort of negative feedback loop. For me? short term antidepressent use is hugely useful for getting out of those negative loops. And really? I don't see a problem with long term medication use, if it's safe and if it helps.