Sound familiar? You're not alone. It's a concept deeply rooted in our culture. We tell ourselves that we'll be happy when we get [fill in the blank]. But when we get it, so often the happiness is fleeting. What happened? Did we pick the wrong thing? Let's try going for something else. But the same thing happens again.
Here's the problem. What we're really saying is, "When I get X, I'll give myself permission to be happy". Well, if you have the power to let yourself be happy, then why would you wait until you get X? Why wouldn't you start immediately? The reason is because you don't have the power, and you won't have that power in the future either... even if you get X.
So, what is this power? Gratitude - being thankful for what you have. Health, family, friends, relative prosperity, and the freedom to pursue your dreams. These are things you probably already have. If you don't appreciate them nothing you attain in the future will change that. Happiness doesn't come from getting what we want. Happiness comes from being grateful... now.