Traducerea - Engleză-Japoneză - I will remember you only while I ...

Romanized
Boku ni wa iki ga aru kagiri, kimi no koto o omou.
Literally
As long as I have breath (life), I will think of (remember) you.

The original is kind of poetic, so I tried to reflect that poetic ambiguity in the choice of words in the translation too.

PS: The vocabulary choices are for the case of a man speaking to a woman.