I want to add, for the younger guys on here, I am in my late 40's and I have women 20 years younger than me hitting on me a lot. There are a few reasons this seems to be true, so I hope this gives you hope and it gives you a start down the right path.
I have always worked out and ate healthy. I am a big believer in stoicism, not searching for outside pleasure but happiness from accomplishment and within. This is a lot easier as you get older and your hormones slow down. But working out, eating right, taking care of yourself, being positive, learning philosophy and applying it to your life, it will allow you to age much more gracefully. Your confidence will grow and your dependence on a woman to feel happy will subside. It is a long path, but one well worth it. Do a workout routine you enjoy, don't make it a chore, make it something you enjoy and you look forward to and it keeps you lose and in shape.
It also seems to becoming less taboo for younger women to date older guys in the USA. I think this is largely due to economic difficulties and reality setting in that a 25 year old guy simply cannot afford a home and a family but a 35+ year old guy can, if he lived the right way. So, save your money, invest, spend every day growing, if a good one comes a long, great, otherwise focus on your financial and fitness goals and the busier you stay, the less you feel lonely.
Don't get into a rush or think your time is limited, you have a lot of time as a man to grow. Many scientists don't belive our brains are finished developing unti our early 30's. So, focus on yourself and what you want out of life and the more you do this, the clearer things become, the more you will know what kind of woman you want and the more likely you will know where to find her.
I know guys in their 50's getting women in their 20's and they are not super rich or being take advantage of. Women naturally want a man, and most men their own age, especially in this society, are not mature enough to interest them. Also, the older guys offer confidence, financial stability, a relaxed no pressure atmosphere, and a go with the flow feeling that women all crave.
Take your time, figure yourself out, and if a woman that fits you comes a long, great, if not, wait until your goals are met and then you can make a move with a full arsenal on your side.