If we all wanted to be happy, we'd be better at it by now. It's like protecting the environment: few people will say they're opposed to it, but it's not priority #1. It's not what natural selection prepared us for.

Your advice is better than the labeling mentality, but you have to take into account that many people will knowingly sacrifice their happiness to something that gives their life meaning: their kids, their religion, their country, their power/business/money/status, maybe even their personality disorder or addiction that gives them an identity.