How Do you Regain Faith In Humanity?

I don't understand how anybody going through the hell that is high school with even a shred of empathy can keep faith in humanity. Everyone around you is a narcissist with absolutely no concern for anyone but themselves. Even the people who pretend to care about you don't have a long enough attention span to fully hear out your issues when you try to explain "what's wrong." Most people get their greatest kicks off the pain of those around them. Being surrounded by all this I can't keep up any faith in Humanity. I feel like nobody actually cares about the people around them. How can someone keep faith in humanity while going through high school?