a friend of mines boyfriends proposed with thee most romantic proposal
your not getting any younger.
i very much doubt this is a rare line used.
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It is about as obvious a line as could exist.
The thought behind it would have to be, "You are going to get married anyway, and your time is running out. Better settle for me, because it's probably the best you can do. IN a few years, you will be old and wrinkly and no man will be interested in you."
True, but unromantic, and the sassumption is that a bad marriage is better than a life unmarried is dubious at best.
I was married twice, for 25 years (of which five were happy) and 6 years (of which 6 months at best were tolerable).