Who am I in your eyes?

I found his notebook when i was searching for something under my bed.After reading through it,I found that he didn't mention anything about me in his notebook.It is not a surprise for me though because I can't find anything about me in his blog and facebook. Now,i realized how unimportant i am for him. I thought when you fall in love, the memory of your loved one will at least stay in your brain. The same question occurs in my mind: Has he ever loved me before? It seems to me that he doesn't remember anything about me or even bother to care about me. The worst part is he didn't even miss me or want to see me again.I am heartbroken whenever I think of that. What have I done to deserve that kind of treatment? Is it because I make myself too available for him? I thought the worst ending will only be a break-up but the truth is even worse than that.He didn't even want to see me before and after the break-up. He went back to where he belongs to and never come back after that.It is as if I never exist in his life. I have prepared for the worst before the relationship started but I don't even know that it is even worse than I have expected. I think nobody in the world will be able to understand my feelings. The injury that I suffer is too severe that I don't even how to heal it. Because of love, i get hurt again and again. How can I ever believe in love again?