I don't know why but sometimes my wife likes to be very revealing and sometimes not. I think it depends how she is content with her body at that time.
Some years ago, my best friend was visiting me. My wife knew that he was here. After she showered she just walked out with her underwear and a see through bra. I was surprised and excited. My friend must have saw her nipples but he has never said something. He is a little prudish by the way and was probably embarassed.
A little bit later, we moved to a new home. After the moving, we gave a party and showed our friends our new home. So they also went to our bedroom. On my bedside table there is a photo of my fully nude wife, which I've shot on our holiday once (pic related). To my astonishment, it did not seem to bother her that everybody can see her nude pic.
At our next home party I turned away the picture before our guest came. When my wife saw what I did, she just laughed and said nothing.