I can't play Byakuya (True Light) anymore....!!! (>_<)

For 7 years....
7 years....
I've been able to play DN Angel's 'Byakuya' (aka True Light)
And everytime I will forget about it and about a year later I will still be able to remember the piece and play it
However....
I tried today.....
And I couldn't remember it!!!
I couldn't even remember the beginning of the piece...!!! OTL
Actually wanted to cry......

This has never happened before!
I've always remembered how to play it even if I forget bits of it to begin with, I always end up remembering it....
Although I still haven't exactly completely been able to play the full piece (since I've always been lazy and my small hands can't reach those octaves) but I've always been able to play at least 3/4 of the piece without any problems!
I have always remember how to play it off by heart without needing the music sheet
but.....
I had to look at the music sheet this time
Even for the beginning of the piece....!!! *cries*

I think I might just crawl into a hole and cry.........
Or I just have to relearn the piece
But it just depresses me....

I guess I'm making too much fuss out of this, but I've known the piece for 7 years!
And it that 7 years, I've never forgotten how to play it...(>_<)
I was totally hoping I'd be able to put myself to finish the whole piece once I've taken my grade 8 exam, and just before I go off to Uni as well....*sighs*

Will need to work hard to relearn the piece! (>_<)