I used to be a cynical misanthrope and actually quite depressed for a few years of my life until I realised I what enjoying what I was doing, I didn't appreciate what I had, and being a miserable person by nature wasn't helping. Now I'm happy pretty much all the time unless something happens that gives good cause for me to be unhappy. I live in a first world country, I'm privileged enough to have a step-dad who's making many times more than the average wage and I have two diferent families that love me, despite one only being step-family. I've got a car, a nice compyter, and plenty good friends. What reason do I have to be unhappy?
That said I'm certainly not one of those relentlessly positive people who tries to see the good part of anything that happens, I'm more just a realist, who realises that most bad things aren't actually that bad so if anything bad does happen I usually just laugh about it. Death and relationship "troubles" are about the only two things I can think of that are bad and I wouldn't just laugh off.