Holy fuck. There's a word for sucking at identifying faces and why people always get so mad at me because I have trouble following movie plots.
I probably have mild prosopagnosia. There's a name! There are other people like me! I took a test regarding celebrities' faces and got 22% of ones celebrities I actually knew of (the average person gets 85%) A few of them I guessed because of the colour of the photo though.
I don't ever, ever, ever speak to friends or smile at people when I see them outside just randomly, because 8 times out of 10 they're actually someone else. I switched schools once or twice a year in elementary school, and it would take me months to differentiate my classmates. (By high school and university I gave up; too many people.)
And I literally cannot tell most celebrities apart. They all look the same! Sometimes I often go, "Hey, that person reminds me of X!" and Alasdair just looks at me and shakes his head and goes, "Uh, they look nothing alike."
I have a few faces mostly memorized, assuming normal lighting and no weird angles, and I'm better at some celebrities, but it's a huge challenge to keep a face in my mind. Even friends I've known for years.
And there's a name for it! I didn't know that! Or if I did, I've forgotten. I always thought I was a bad person or something for never being as good at facial recognition.
(It's also why I get annoyed with people when they comment, as I mention I'm terrible with faces but do remember their name, "Oh, I'm great with faces and terrible at names!" Of course you're worse at names. EVERYBODY is worse at names. I'M (usually) the only one that can't tell faces apart, which is embarrassing and a pain in the butt.)
I don't know of anyone else like me though? I can't imagine what it would be like to have a more severe form!