I watched a really good film about this principle a few years ago...
Cant remember the name, but there was this woman (I wanna say 'Sandra Bullock' but I'm prob wrong) who had the same thing...
She couldn't remember what her Husband looked like - He was played by diff actors throughout the film, to give us her 'point of view' - But it was really good...
She tried using all sorts of tricks to recognise him - Like giving him a distinctive tie to wear and stuff as a b-day pressie...
Like I say - The name escapes me - But if you can find the film, it was worth a watch
EDIT:
FOUND IT! "Faces in the Crowd'...