I was cheated by the girl I loved the most and cant get over it,, IIN?

I am no psychopath! But yes I really did feel like killing Bruce, and still do. And I will kill myself before the thought of killing Sally ever comes to my head! But I do think I know the real reason behind her ditching me. I knew there was something wrong with her, a while before I finally caught her, but my mind was blinded by my love for her and I smashed all my suspicions to dust. Even now my eyes dont want to believe what I seen, and I am upto talking to her at first opportunity, but she avoids me at college. Perhaps its because I am immature for my age. Everyone, including her said I was kinda childish for my age, and maybe thats why she liked me better when I was younger and ditched me when she became more matured. But no matter how hard I try, I cant forget her and she will be my true love even when if ever I am with someone else.