Sheldon, it sounds like you have a good life and appreciate it, so good for you!
I was thinking just the other day that if we do one, our high school class 60th
reunion is next year, and in my case, it is remarkable how few classmates have
passed. However, I live in a university town, so not only are new residents I
might meet not here very long, but most of my h.s. classmates left town right after
they finished school. And you are right, it is very hard to make new friends at this
age.

As to the OP, I don't think he is being too control-freaky, but I think the solution to
empty the pantry is a good idea. Rat poison is a very bad idea, but leaving a
clearly-labeled box of ant poison on the shelf might give the BN the idea that you have a
bug problem and have to keep the food elsewhere, which you could explain if she asks.
Put the contents of your pantry in your garage, leaving the spices, flavorings, etc., that
she wouldn't eat anyway. I have no idea what to do about her taking other things if
she wants them. She obviously needs professional help.

I think since she is your wife's relative, that your wife should talk to family members
about finding a way to convince BN to get that help.

N.