That's the first thing my grandma said to me today when I saw her. I haven't seen her in a month or so. I thought I was getting yelled at for not coming over. But she said, "Your face is so thin."
Then I went back to work and told the girl I work with. I was so happy. I said,"I don't see it because I look at myself all the time." Then she said, "I don't see it either." I about died!
So I picked my mouth up off the floor and kept on walking!
While she didn't say it in the best way or think about the reasons, I think your co-worker doesn't notice it because she also sees you every day.
Your grandmother sounds so sweet! One Christmas, mine poked me in the stomach and greeted me with "Well, I see you stopped going to Weight Watchers." Um, Merry Christmas to you too, Grandma!