People are going to fail you...so many people will probably fail you in your life, that they won't be worth your time anymore. You cant keep people around that failed you big time, like damage your mental/emotional state by constantly playing with your feelings or not being there for you, when you need it. Your life is your life, you have a chose to who to keep around and who you would consider a friend and so on. People may nag you, or complain about some things about your life, but there is a difference between want they want for you up to their standards and what you want for yourself to better yourself, considering not always on the same page.
It's unavoidable for you to be screwed over or people failing you, but you will learn a time goes by, who is worth it and who just making you wasting away your true self. Not everyone will be compatible with eachother either as people can be better friends with someone than someone else. Look people do suck, a lot do, but most people stil have good things to them, even if it's a small thing about their personality, but their will always be someone who show you that they actually care and won't majorly fail you, since just click well and can talk about anything. I mean people will make small mistakes and small fails with you like might say the wrong thing on accident or like hurt you by hitting you in a the face with something, since meant to throw something near you, but aim was off.
Just don't shut yourself out from everyone...it doesn't work. I get you are hurting and so on, but you still deserve to live your life,and have people that care. So just make sure you aren't draining yourself fro others badly, but make sure to care for others that do the same for you. Trust me, the people who care will always check up on you and feel bad that you are feeling down too, that might not be able to say anything to make it better sometimes but at least know you need someone there that hasn't let them down.