Friends: Some people will just be your friends just to use you. I know that from experience, and I know that hurts deeply. I've been stabbed in the back ( kinda literally ) by them, it hurts and you have to move on, and learn to differentiate the two types of friends: those lying bastards and your true friends.
Family: Everytime I get into family reunions and every other day, I go through quite the mental torture. It hurts especially when they use what you trusted them in keeping a secret and you safe, against you. It hurts deeply and you need to let go of that, but thats the hardest thing to do
Lovers: If they only love you because of something you have that they need, dump the bastard. If they cheated on you, well, they are the coward and you aren't, you shouldn't feel that guilty. Funny Thing: My Ex Girlfriend is my Best Friend, and even after the breakup we are still great friends. If there is anything to take from the previous sentence, it is: Love someone that you know will be straight with you when they don't feel ok being in a relationship with you and learn to let go if that happens. Don't learn it the hard way anymore.