As people have said, you've yet to grow and gain experience yet. I'm sorry you feel pressured at your age to gain a better understanding of something like this. You could read up on the topic but it may just serve to confuse you further. My advice would be to get your depression treated and carry on enjoying being young and free - there is so much time for you to figure out who you are so please just relax and enjoy the lack of complexities these parts of adult life contain - it can be no fun at times!