Well, I think you only need look at those celebrities who definitely aren't hurting for cash (or fame), but who fall into a series of bad relationships, strange cults and unwise investments, or visit a third world country and see how happily the children play together, to see that having money doesn't automatically make you happy and being poor doesn't throw everyone into depression. But those celebrities, you think, are just foolish. You would know what to do with all that money, right?
Well, the studies show that in poor countries, being "well-off" does lead to greater well-being; but, by well-off, we mean having access to food, rest, shelter and social contact. The surprising thing is that, after those needs are met, money doesn't have much effect on happiness at all. Once you have your basic needs met - and that might mean having somewhere to rest your head and clothes on your back (not "basic" as in two cars, a home cinema and a swimming pool), that extra money will do nothing for your happiness. So, in affluent societies (where everyone is doing OK), there's no real connection - once you have enough to live comfortably, extra money won't bring you more joy.
If you secretly (or not-so-secretly) dream of winning the Lottery, it's bad news again - Lottery winners are likely to experience overwhelming happiness at first, but to return to a similar mood to before their win a few months later. Why is this? Well, I'm sure you've read stories of Lottery winners blowing all of their money on gambling and drugs, and although most people are a little wiser, having such an unexpected amount of money is still likely to lead to some bad investments. Failing to plan ahead can mean that the money disappears pretty quickly, but even if not, that sense that you didn't truly earn or deserve the money can eat away at you. At least having that sense of pride from earning your money yourself can help a little in the self-worth department.
Still not convinced that a few extra thousand would make you the happiest person alive? Take this study - since 1957, the numbers of Americans who claim to be very happy has actually gone down. More and more young people are depressed - and yet, while the price of things has gone up, the average wage has increased so much that people can now afford two nice cars instead of one. If it were as simple as "money=happy", surely the number of happy people would have doubled (see David Myers's work for more information!).
So, what's going on? I think to answer this you can start by asking yourself one simple question - what does money mean to me?, or If I had more money, what would I get? As we said, if you want money because you are not able to satisfy your basic needs - food, housing, bills, medical care, clothes - then it most likely will make you happier. But once those needs are satisfied, those extra digits on your bank balance are unlikely to bring more than a fleeting moment of happiness.
Money is about what you can do with it! What is it, otherwise, but pieces of paper or numbers on a statement? The number on your bank statement does not tell the world how worthy a person you are. Money is only as good as the things you can do with it... so perhaps you want more money so you can eat more nice meals out? Go on more holidays? Start up that business you've been dreaming of? Or do you just feel that you need "nicer" clothes?
The clearest explanation for all of this is Maslow's hierarchy of needs, and I'm going to introduce you to it now if you're not familiar with the idea. Through our lives, we try to build this pyramid and to reach self-actualisation, which can be seen as the pinnacle of happiness, being at peace with yourself. But we can't build one layer until the one below it is firmly in place. The bottom layer covers those basic needs I mentioned - food, water, shelter, clothing, somewhere to sleep (our survival instinct, really). Only when those are met do we start to worry about health, employment and family - still things that money can help with. Of course, layers can collapse during your life, sending you back to square 1, but generally we climb our way up through our lives - and disappointingly few people reach the top.
Is money mentioned there? No - the things that we need to work on once money covers our basic needs are our friendships and relationships, our own confidence, and finally our sense of creativity, morality and sense of purpose in life. What this means, I'm afraid, is that all the designer handbags in the world won't fill the void in your soul. Once you can get by, financially, your focus shouldn't be on accumulating more wealth, but on your sense of worth, the connections you have with the people around you, and the meaning you ascribe to your own existence. You could just buy some new shoes and hope it all goes away, but I think you know full well that that hunger inside you is never satisfied by retail therapy or hoarding your cash.
So, what's the answer? Well, ultimately, money provides one very important thing - freedom. Freedom from debt, yes, and the freedom to do what you want without struggling to pay the bills the next month. When asking yourself why you really want money, what reasons did you come up with? How could you achieve those things now, without having a lot more money? If you want money because you want to travel, look up cheap alternatives - take a long bus ride instead of flying, use Couchsurfing instead of hotels, eat supermarket food instead of going to restaurants every night. If you want money because you like to eat out and sip cocktails, look at mid-range, nice restaurants, which can often be better than the very expensive ones, and check local websites for vouchers offering discounts on certain nights. If you want more money because you feel that your friends look down on you in some way, then perhaps that "love and belonging" part of the hierarchy of needs is what you really should be looking at - are these friends who really make you happy? Are they really looking down at you, or is that something you're imagining because you look down on yourself?
In conclusion - if you are already meeting your basic needs (and, OK, maybe a little above) more money won't really make you happier. A lot of the things you think you need money for can be done on a lower budget, if you find out where to look and get over the idea that expensive=high quality. Money is only worth what you can do with it. Your sense of unhappiness might not be from a lack of money, but because you need to feel that your life has meaning or that you like yourself. Your relationship with money can be very complicated, and can actually stem from your parents' attitudes towards it.