Here is my pure translation:

Pleasure of love lasts but a moment,
Sorrow of love lasts all of life.
I have left everything for the ungrateful one, Sylvie.
She leaves me and takes another lover.

Pleasure of love lasts but a moment,
Sorrow of love lasts all of life.

"As long as this water will run sweetly toward this meadow which borders on the prairie,
I will love you," Sylvie would repeat to me.

The water still runs but she has changed.

Pleasure of love lasts but a moment,
Sorrow of love lasts all of life.