This happened to me many years ago when I still worked.
I walked into work one morning after my husband had left me and the boss called me into the office because I didn't walk in with a smile on my face.
I don't think bosses have the right to tell their employees what facial expressions they should have on.
The bosses don't know what goes on in our private lives and I know that I didn't want to discuss it with him.
It's very unnerving in my opinion.
Wishing you the best of luck,
Boopers