I was there where you are now, and I wrote a poem just like yours. I know how it feels, to be ignored by your once-best friend. That hurts because you know he is the only person who'll ever understand you.
well, maybe the truth is that he has changed with all the others. That's not your fault and know there is nothing you can do. Maybe one day he'll realise he needs you, but maybe on that day, you would already have moved on. Forgive and forget. It's all right. Things change, people change, but you have to learn to let go and move on. Remember that in 50 years, what you'll remember won't be the hurt but the friendship and all the good times that came with it.
Good JoB!