This happened in July, 2012 in my parents' house in a small town in Upstate New York. This would happen probably two or three times a week, then not happen at all for some time, then start up again.
I would have these dreams that something is in my room. I would wake up and discover that I'm trying to follow, catch, or defend myself from whatever it is. Whatever "it" is I could never say. It was small, no bigger than a fist, indefinable, and I could never really tell what it was. I never thought much of this; I thought that it was just dreams, and that maybe I was freaked out about bugs or something.
Then one day I was sitting downstairs watching House Hunters with my mom, and something really unexpected happened. To the right side of the TV hangs a picture that my grandmother gave to my mother of two eagles soaring over a foaming white river and waterfall. I could not see the picture from where I was sitting. It's in the corner of the room, perpendicular to the TV, right at the foot of the stairs. The only thing that's visible is the frame.
Suddenly, as I was watching TV, I saw these white, transparent wings, flapping, but floating downward from the wall where the picture hangs. I didn't see a body, just two wings. The way it moved it almost looked like tissue floating in the breeze, yet there was a steady, flapping. It glided downward past the half wall that is the railing of the stairs.
I didn't get up to see what it was. I was frightened, truthfully. I did check the stairs, for tissue or something later, but didn't find anything. I believe it was what I was seeing at night. Then a few days ago I discovered the picture of the "Wedding Dove" from the photos on this site. It looks exactly like the thing that I saw.