1. Keep it real. I have learned that everyone is going through stuff in life. If you share (within reason) yourself and your fears and anxieties, it helps bridge the gap between people. It helps make friendships, and it makes you more empathetic of other people's troubles and situations. Listen when other people share their feelings. Share yours. Make a connection. You don't need to always pretend that everything is perfect.
2. Let it go. Sometimes you have to just not care about other people's drama, troublemaking, juding, and just plain jerkyness. Some people will never be happy and you can't change that. Shrug it off and don't let the miserable people bring you down. Try to develop a thick skin because a$$holes are everywhere and you can't totally avoid them. Be the better person and you will come out ahead. Don't stoop to their level or get involved in the drama.