What a nuisance! I like the post above about having the uninvited guest escorted out. You do have that option . . . even without setting up the secret code word, etc. All hospitals have security officers, and that is part of their job. You tell a nurse that the woman is causing too much stress and you need her out of there. The nurse will have a security officer escort her out, if she won't leave. Sometimes you have to go a little nuclear to back some people off.

What's really galling is that this woman seems to know perfectly well that her coming out is unwelcome . . . and she doesn't care. You're right to hang back a bit. Ultimately, this is between mother and son . . . though a sick guy deserves support and help managing intrusion.

"Intrusiveness" is a classic hallmark of certain types of personality problems. With these types, you really have to draw a line in the sand and consistently defend it. They never accept "No" and test every boundary. One hates to seem rude, but being rebuffed doesn't really bother this type, or they would have backed off long ago.