Miss Manners 6/15

DEAR MISS MANNERS: Several months ago, my cousin invited me to join him and his wife for a night at the theater. As I am single, they also asked if I would mind if they brought along a young woman, to which I said I would not mind at all.
The woman they introduced me to seemed nice enough but I found her to be much too young. I am 33, and she was only 20.
She wanted to see me again, so I tried to explain as politely as possible that I was not interested. Since that time, she moved in with her mother and daughter directly across the street from me. I assumed that we could be friendly.
As it turns out, this has become very difficult. If she happens to see me pull into my drive, she will come over and knock. If she sees me mowing or painting, she comes over.
I work nights, and she was knocking at my door at 8:30 this morning. Worse yet, I understand that my cousin and his wife are still encouraging her to pursue me.
She asked me again why I wouldn’t date her. I want to be as polite and understanding as possible. What would Miss Manners do?
GENTLE READER: You have fallen victim to a falsehood perpetrated by the crowd who tells everyone the truth, even when they know it will offend – namely, that being polite means never saying “no.”
To this, Miss Manners says: No. Being polite means knowing when to be frank and when to elude.
Sit your young friend down and tell her, firmly but kindly, that you are not interested in a romantic relationship. Then repeat the phrase as often as necessary to avoid giving any specific reason, such as her age, which will only give her a basis to argue.
DEAR MISS MANNERS: When our family dines out with my husband’s mother, she often picks the restaurant and pays. She asks me what I am ordering and then makes snarky remarks.
I do not comment on her food choices, ever. I have never ordered an outrageously expensive item from the menu, so price isn’t her reason for asking.
Would it be impolite or dishonest to respond by saying that I haven’t decided what to order yet, or something equally noncommittal? Or is she entitled to express an opinion about my meal choice if she is paying?
If that’s the case, I will continue to ignore the snarky comments, since we don’t see her often.
GENTLE READER: There is a common misperception that paying for something entitles one to be rude about it. Miss Manners is aware that there was a time and place when one could buy religious indulgences to relieve the bearer of the consequences of sin, but there is no such thing as an Etiquette Indulgence.
Telling your mother-in-law you are still deciding is not rude, and any minor transgression against honesty is paid in full by removing temptation from her.
Please send your questions to Miss Manners at her website www.missmanners.com.