Yup: http://store.steampowered.com/app/57300/ (Side note: in searching for that link, I found out there is actually another franchise called Amnesia: http://store.steampowered.com/app/359390/)
Well I'd imagine it feels like you're forgetting something, except it's very obvious that the thing you're forgetting is majorly important and not remembering it disrupts your day-to-day life and thought processes.
That sums it up about right. Just about my entire life is disrupted. It's very awful waking up in a hospital with just about zero memories… and just as awful not remembering anyone - relatives or friends.