This is probably incredibly shallow and male and white of me, but I have to admit that every so often I just straight-up forget how beautiful my partner is. It has to be at least partly because I can't believe that someone so beautiful would be interested in me, and at least partly because I have a terrible memory, and probably partly because I'm pretty self-involved and self-directed by nature. But yeah, I'll be sitting around and I will just plain forget that my wife is beautiful.
And then I'll see a picture, like this one:
Or she will come home from work and I will get up from my desk and she will take off her scarf and say "Hello, Husband!" in this fantastically posessive way that never fails to make me smile, and I will see her and suddenly remember all over again how beautiful she is, and how amazingly glad I am that she is a part of my life.
I don't want to forget, but sometimes I do. And the best part of that is when I get to learn again how lucky I am.