Sleepless nights

I get upset with myself when I let my co-depedency affect me at night.  There is nothing worse than circulating terrible thoughts through my mind, about my sister, before I go to bed (if I can get to be that is).  Last night I had to get up and read a book for an hour to get my mind off of her and onto another topic.  Even still, once I could barely keep my eyes open I went right back to thinking about her, and then sure enough I get to see her in my dreams.  Seeing her wouldn't be a bad thing if I saw her in a positive way, but I visualize her giving herself needles or hurting herself and I have to sit and watch her when she does it.  I don't know why this happens to me, but it makes me wake up thinking about her.  I've grown up believing things happen for a reason, so I have to brace myself for what may come of this.  I can't believe that's another thought that crosses my mind, it's terrible.