I'm only 19, so I definitely haven't learned all that I will about life (I've hardly learned how to spell the word definitely), but I've collected a small amount of knowledge on the world and about myself, especially within the past couple of years, which I'll explain below.
One of the main things I've learned is that you have to be willing to go along with the natural course of your life. It's easy to be angry when things don't work out how you want them to or how you imagined they would. Even though being angry is our body's natural response to hardship, and it might help combat initial feelings of sadness, it doesn't help the situation suddenly improve or make us feel any better about ourselves. As hard as it is, letting go and accepting life for what it is is the only way to get past our difficulties. Once we acknowledge our position in life, we can start growing from where we were planted.
Secondly, I learned that growing up means being alone a lot of the time. It doesn't make you a lonely person, it just means that you're learning how to be okay on your own, and everyone else you relied on—namely, the friends you liked hanging around—are doing the same thing at the same time. You'll find that as you get older you have to pursue your own interests, separate from others, and the kind of confidence you have to develop to do so is something you build gradually. Being alone is uncomfortable at first, but once you realize that it's part of our natural process of growth, it is less daunting and more natural.
Thirdly, guy friends are the best friends. All of us girls do need to stick together and it is us against the world, but still, guys are the best. They seem to know exactly how you feel without you having to say too much, which is weird because we all thought they were emotionally unintelligent. They're not. They don't pry things out of you or ask you seven billion questions about how you feel, but somehow, it's easier for you to open up to them. They'll be straight with you about everything because they're not afraid to hurt your feelings. They'll buy you pizza without secretly, hostilely waiting for you to Venmo them. They'll do stupid things that your girl friends wouldn't want to do with you, like singing in the stairwell. They distract you from all the crap that girls have to deal with, like feelings. That's all there is to it, guy friends are the best friends.
The last thing I'll share that I've learned is this: the only way for you to be a good friend or a good daughter or a good whatever is to be good for yourself. I've always concerned myself with making other people happy, especially those with whom I am closest. In order to make them happy, I would stretch myself thin, trying to maximize the greatest amount of happiness for the greatest number of people, no matter the toll it took on me. However, that ended up backfiring on me because at the end of the day I was burnt out and I couldn't be fully present with any individual person, which made my loved ones sad: the exact opposite of my purpose in life. Your loved ones don't want you to make them happy, they only want to see you happy. They want to see that you're enough for yourself and that you are well, and being well allows you to be fully present with them.
I guess I've also learned that learning takes time and learning takes pain. Every day we are growing, everyday we are experiencing things that turns what we thought we knew on its head. The only disservice we could do for ourselves is to not recognize this natural process of growth, and to not go along with it.