Laura, that's funny! You mean things your partner can't see? Because of how they look or because of their emotional value?
I do keep an item that belonged to my husband for sentimental reasons. A long time ago we lived apart for study reasons and he gave me a big 80s sweatshirt to "hug" me from afar. I still have it and though I don't wear it anymore (my L.L. Bean fleece is warmer and comfier) I can't find the heart to part with it.

K.M that's so sweet. Does he know you have it?
Often we are apart for our work. I have a special stash of his old shirts in the way back of our closet. I wear these around the home and at night when he's away. One day I would like to have a boudoire session for him and of course I'd wear these as a surprise to him. I think it would make a great romantic gift.

I'm not sure if he does! And the thing is, we're so pressed for space where we live and that big ol 80s sweatshirt takes up half a drawer. I still keep it!