[Ryoko]

better translation:

i wanted to say thank you,
but i couldn't (say thank you)
(not sure of the last line, its something like: but then, in that case, it's as though it's the eternal farewell)

because it's too sad,
someday, again, i will be reborn
and probably set out on a journey to search for you

Something like that, I haven't been studied Japanese in a couple of months but thats the basic picture, I'm sure evolusean will come up with a much better translation.
romaji:

arigatou to iitakatta
arigatou to ienakatta
datte sore ja maru de eien no SAYONARA mitai de

kanashisugiru kara
itsuka mata boku wa boku ni umarekawatte
kimi o sagasu tabi ni deru n darou