Endorphins, serotonin and their friends are the happy chemicals in your brain. When you have tasty food, they are released. When you get attention that you desire, they are released. They are mechanism by which a naughty child learns to be naughty to get attention - she gets a happy rush when she gets attention, and if her parents give her that attention when she's naughty and ignore her when she's good, she has been trained to be naughty. Why?
Because we are all addicted to happy chemicals
It's the only good addiction, and it's the root of all those psychological addictions (not the chemical ones). You have somehow learnt that there is only one thing that will give you that happy rush right now, so that's what you indulge in, even if you know at the back of your mind that it's not right.
So are we all hedonists, just doing whatever makes us happy? To a degree, yes. Many hedonists are just doing whatever makes them happy. There is a kind of logic that if you are doing something that makes you happy but which is damaging your future (like spending all your money), then you will be storing up unhappiness, so you try to fit your hedonism into a longer-term picture.
But you can train yourself (or be trained) to seek some future goal which will make you happy, or to change your values so that your happiness depends on something else. So I can pin my happiness on academic achievement, so I work to do what it takes to get that goal, in order to get that happiness waiting for me. This is what hedonism lacks - the willingness to change what makes you happy. For hedonists, happiness is the goal itself.
For me, that's a problem. Chasing happiness itself means that if I find a way to get a steady drip of happy chemicals then I should take it. So if I was offered a lifetime on a cocaine and morphine drip, then I should take it. Happy ever after, right? No, I want more from life than just some happy chemicals. I want to make a difference, I want my genes and memes to survive, to live on, to improve the human race and its future. Maybe that's some successful memes showing through, enslaving me to their goals, maybe it's just common sense not to want to end up as a body in a hospital bed with an ecstatic smile.
Choosing a new goal
So an ecstatic smile is not a good enough goal. What is? I'm a husband and father, so I want the best for my family. I want to support them, house them and feed them. I also want to inspire my children to live joyful lives. I want to make a difference to the world, not just live a quiet life in the corner.
So if those are my goals, I need to pin my happiness on them, so that I learn to derive happiness from the steps I make in that direction, in pursuit of those goals.
I could do with losing a bit of weight, being a bit more focused at work and at home, having more of a plan. So I'm defining some medium term goals, setting aside reasonable amounts of time for them, planning to succeed. I lose focus when I can't see my efforts leading to some worthwhile goal, so I'm weaving these goals into a longer term achievement.
Often people fail with long term goals because circumstances change. Aiming for that job or that dream may make sense now, but not work out when you get there. So the goals have to be largely about how you are improving yourself and your circumstances, not about achieving specific targets that may move. Fortune favours the prepared, so aim to be prepared.
Jobs, companies, houses, all pass in the night. Getting attached to any single one is easy, because of all the improvements to your life you imagine will result. But the key is to notice what they mean to you, what you yearn for. Sometimes it's recognition, self-worth, belonging; if you realise it's one of these then they are better (and more cheaply) worked on by addressing the real issue rather than seeking the answer in purchases or jobs, which won't actually resolve an underlying emotional problem.
So this is me working out what I actually want to achieve, what will make me a happy man in the long run, and trying to avoid the pitfalls of vainly seeking fulfilment in jobs and purchases, taking an active approach to getting to where I want to be.