I haven't heard that version in a long time but I'll take a guess. I find Belton is hard to understand at times because of how he slurs and distorts the pronunciation at the ends of lines especially--like country singers do many times with the "r" sound in American English.

"Mon (or ton) amitie va tout l' temps d'etre"

(we don't usually pronounce the "re" endings...so it sounds like "det"...and then he slurs it and it sounds like "dur"

The English to Mathilda is "Your love for me will always be..."

This is just my guess...it could be something else. Like I said, I don't have the record here to listen to.

I've never heard the song, but could it be ".. tout l'temps endure"?