I have been having huge difficulty lately with my fifteen-year-old sister who is two years younger than me. There are occasional moments when we get along, but the rest of the time she is very negative and acts as if she loathes me. At everything I do she insults me, and she shoots down every opinion I have. I try to be friendly to her, but she tells me not to speak to her or be around her or ever smile at her. I have tried doing what St. Therese did with the difficult nun in her convent, but if my sister sees that I am making an effort to be nice she becomes furious.
She acts with this hostility to the whole family, including the little ones, who understand that they are not permitted to touch or kiss her. But the strange thing is that once she is in public or interacting with anyone outside our family, she becomes as docile as a lamb and extremely quiet and even unsure of herself. When she speaks about these other people at home she proclaims how much she doesn't like them. And in her strange rare moments when she suddenly becomes nice, it's as if she is a totally different person. I like her a lot during those moments. But then she goes back to acting as if she hates everybody, especially me. And I just don't know how to respond to it.
Should I just leave her alone? Since she acts this way I feel that she can't be very happy, and so leaving her alone doesn't seem right. Or should I try the same thing St. Therese did, being especially kind and acting as a friend? When she tells me not to speak to her or look at her should I obey out of tact? Maybe if I irritate her so much that would be the kindest thing to do. I just don't know. Since she is my sister, and we do have to be around each other every day, what is the best thing to do?
As for why she hates me, I don't know. Perhaps I have big personality flaws I'm not aware of. Most of what she says is, "You're stupid," because I have different ideas about things than most people our age do. She also doesn't like it when I display any enthusiasm about anything.
I wish we could be friends, like we were when we were little. I wish she would change so that our family could be peaceful, and so that my 9-year-old sister would stop copying her behavior. She's beyond my parents' discipline. Is there anything I could do to help her become happy again? She's so guarded that she doesn't let anyone get close to her. She hates it when anyone tries mentioning prayer or anything to do with God to her, but I feel that God is just who she needs. But I feel that I am the wrong person to try reaching out to her. I know I should pray for her, but when it comes to dealing with her in daily life I am at a loss.