I don't think it's a black and white issue, either. I think if there's something that's bothered you for a long time and fixing that thing and that thing alone would make you feel better, or make you feel like the person you are on the inside, go for it. However, if it really is low self-esteem, and you'll never be happy (ala Heidi Montag) or some sort of deep-seated self-loathing because of childhood issues (ala the entire Jackson family), get therapy rather than surgery. You looked fine before.
What really scares me right now, though, is all the fillers and injectibles. To me, those are screwing up more faces than all the surgeries combined. The trout pout, the immovable forehead, the weird, pointy jawlines, the chipmunk cheeks. They're all making people look non-human. Yes, we'd all prefer not to age, and I understand wanting to slow the clock. But you don't look younger. You look "done." You look fake. And you lose all ability to see that you look fake, and keep going.
Having said all that, I'm doing all I can in a preventative way, to face the next half of my life with grace and dignity. I get enough sleep, take my makeup off, moisturize, stay out of the sun, get vitamins, etc. But if there was ever a point when I started to look like a wrinkly old crone, my vanity would make me get a tasteful lift. My outside needs to match my inside. I can take a few lines here and there, but when things start sagging beyond my control, you bet I'd take matters into my own hands.