Being at such a young age, sometimes things can really get overwhelming. I remember going through similar things at 15/16. But looking back, I now realize that the thrills and ups and downs of the teen years PALE in comparison to what you'll experience in adulthood, and I'm only 26! Things have a way of appearing exaggerated through teenage eyes, but it's only because you're still trying to discover yourself and find your place in this world.
Like you've said, remaining focused helps you to not lose your way throughout all this. But the most important thing to realize, is that all of this is just a prelude to life. It might seem impossible now, or overwhelming, or you might feel like giving up, but trust me, you have to know and stick to your priorities and forget about the distractions.
Friends are great. They make you feel wanted, belonged, socially accepted. But nothing's worth allowing yourself to be mislead or mistreated. If your friends do these things to you, then they're not your true friends and you need to sever those ties. They're already plenty of people out there willing to acccept you for who you are and what you are without judgement. Just be patient - all good things come to those who wait, and I'm a living testament to that.