Okay before anyone will judge me quickly stop and hear me out. I know it's incredible wrong and it makes my stomach crawl but I haven't been brought up with my sister (half), we share the same mum but I went to live with my dad near his job. Since we were younger we would see each other monthly but then it got to once every 3 months. Please understand I've not had a stable family life, I have no other siblings and no friends and I'm incredibly antisocial. My sister is exactly 16 months younger than me (I'm 17 as year) and I hadn't seen her for quite a few months like I really didn't care too much about her until we had a family wedding and I got this empty stomach feeling that I can't describe but I was so attracted to her, she was all idk like womanly? Does that sound stupid and I couldn't believe I was related to her and I'm so ugly - fast forward abit I asked my dad if I could stay at my mums over Easter 2016 and I literally loved it when it was just me and her, we would watch films together, I would help her with her homework and I even met her boyfriend who i am really idk envious of. I feel bad because I know this is wrong like I have really bad urges to just make love to her but I do no I really do this is repulsive. I did asked her to kiss me and she did on the cheek but I felt I wanted more. It hurts me all the time thinking about how much I love her and I know my mum would have a heart attack if she knew, I don't know what to do I can't eat nor sleep I just want to kiss her, have sex and I have come so close to losing control of myself that I don't see my mum anymore. I literally don't know