To think they are still doing it!
It was the bane of my teenage years, as no, I rarely had a boyfriend.
And guess what? When in my late twenties I began to despair of finding anyone who would want to marry me and have children, did any of those busybodies volunteer to introduce me to nice young men?
No, they did not!
I am willing to bet that if, OP, you hadn't given your friend an answer that politely told her to mind her own business, when the day comes that your daughter has a boyfriend, that good woman would be all over it with impertinent questions like, " are they getting married" or "is there a baby on the way".