I'm the problem?

Of corse it's me. Not my greedy, self absorbed sister. No, she's an angel in my parent's eyes. I have a psyc history, I'll be the first to admit that but she tries to make me snap. You have to work to het into my good graces and she let's any one in. She dates anyone. Then can't understand why she gets hurt so much. She may have book smarts but not an ounce of common sense. This girl takes pleasure in making my life a living hell. But I give it back to her. Though I'm a little more underhanded. I take things from her and hide them, or just take things from her. Like money, make up (I don't wear make up), ect.