A lot has been said about the power of positive thinking, I believe that to be true. Believing in yourself, your character and strenght is the first step into achieving your dreams.
But I happen to believe that the only way to be truly happy is when you are on the path towards your dreams, it seems that it's easier to complain than to actually make plans and take action, but if you spend your whole life complaining, it is safe to say that you'll never achieve anything, why? you may be able to think positive for a little bit, but when your lack of actions cause NOTHING to happen, nothing improving in the path towards your dreams, you'll loose focus and determination, and finally happiness.
Being a perfectionist and slightly obsessive person, taking action gives me peace, because I know that I'm on my way and not wasting my time, I may not arrive to my destination, but I'll be fairly close.
For example: I love writing, I started with poems and then later in life, realized that I considered my sense of humour one of my biggest qualities; in order for people to like me and enjoy my company, and then be my friends, they need to understand my sense of humour and think of it as funny, interesting and entertaining and not plain mean or demeaning (this topic is so broad it will have it's own blog, stayed tuned). And I decided I should take advantage of my sense of humour and my love for writing by....writing a blog of course. Sure, I'd love to be a best selling author, quit my day job, write and write and be famous; but for now, I'm happy with people reading my blog, enjoying my sense of humour, and sharing with people that have similar interests to mine.
I am closer to my goal of being a writer, that makes me happy. When people compliment my blog, I love it! I'm using my talent. I am taking action.
The same principle applies to anything that you enjoy in life, it is never too late to start. It might be difficult to get off your butt and start working on it, but the satisfaction is totally worth it.
So GET.OFF.YOUR.BUTT, start looking for a more rewarding job, start training for a marathon, do more charity work, loose weight, gain weight, etc, etc, etc. Even if you only accomplish 10% of your goal, just walking in that road will make you happy, the road of your dream.