Unfortunately, I don't remember much about the movie.
It was sort of about a man and a woman getting or being together. And in the end the woman lost her memory somehow. (maybe even by him? Or on her own behalf?) One of the last scenes shows her randomly walking by the man on the street but she doesn't even recognize him. He does recognize her but decided that it was better to leave it at that; I don't remember why. I also don't remember how the memory loss actually happened.
I watched it like ~10 years ago in German TV, however it looked like an American production.
I believe that he knew or even caused the memory loss on her because he knew it was better for her; even if she wouldn't even know him anymore after that.
Maybe she had memories of some kind that really screwed her up and it was so bad, that in the end he decided to get her memory erased, even if that means losing her, but she would feel better.
As far as I remember the movie had a really great story and I wish that I could find and watch it again.