Being in your late teens and early 20s is hard, navigating sudden adulthood and responsibility is difficult and trying for anyone. There are those people that embrace it with grace and dignity and some who fall flat on their face their first few tries and then there are some whose transition from childhood to adulthood have a lot more help than others. If you do not happen to have a lot of help from others, chances are you do it all on your own; you work, pay bills and take charge of your own education because if you don't, no one else will.
It is hard being someone that has to do it all on your own. Watching everyone else go to parties, go on shopping sprees, travel the world, and do pretty much anything else they want to do, without worry, is tragic and depressing to the ones who must be financially independent. It is hard to watch those with no responsibilities live their life when you are stuck constantly working, going to school and doing school work on and endless, tragic loop. It will eventually get better, things will become easier and you will be able to take a breath without worrying about what is going to come next, but before then, here are a few words of advice that will come in handy during this time.
One thing to always remember is it is OK to be a little irresponsible. If you have been planning a trip and want to spend some of the money you earned on a much needed vacation, do it. Buy that blouse you have been looking at for months but did not think you could afford and wear it with pride. Buy that five-course meal and enjoy it, go out to the bar and buy a couple drinks. Relax every now and then and enjoy the small things that everyone else over indulges in. You work hard and deserve it every now and then.
Another thing to remember is that you are so strong. It takes a lot of passion and drive to do it all on your own. All the exhaustion, time and stress will all be worth it some day when you can look back and say you did it, you did it on your own when everyone thought you would fail. You can feel more pride and happiness knowing you took care of yourself and succeeded on your own valuation.