I always thought that there had to be at least a thirty year age gap before you could address someone other than a spouse or partner as Darling or Sweetheart. My grandmother called me Poppet, my mother called me Old Bean and my father called me Sweet Pickle. None of them are lovely, are they? For a short time I envied the girl down the street whose father called her Princess. Other childhood observations brought to light that old women were sometimes called Dear by service or health care workers. Even as a child I knew it was patronizing. If any young perky thing calls me Dear when I'm hospitalized with old agedness I shall swiftly make a connection between the impudent young thing's head and the bed pan. I intend to be a cantankerous old thing. Don't Dearie me.
Of course I'm telling whoppers. I'll do no such thing and I probably will be a sweet old dear, doddery and confused. I call my students Sweetheart or My Love quite often, and I truly do mean it. By November I have fallen in love with them. Terms of endearment should be used honestly. Do you really feel affection for this person you are addressing? Is the affection likely to be returned? Do you know each other well or have you had such a longstanding aquaintanceship that there is a history involved? I had a very stiff and formal grandfather who didn't really know how to interact with children other than that they should be seen and not heard. When I was around eighteen he began to call me Darling. It is also what he called my grandmother and my mother. It seemed natural that at that point I belonged with the adult females whom he loved and I had graduated to my new title, Darling.
On the other hand, unlike my grandfather, you may be a natural ebullient and flamboyant person, and terms of endearment may be part of your style. I remember as a little girl watching Zsa Zsa Gabor on television calling everyone Darling and I thought it was quite funny. My friend and I imitated her when we played.
"Daaahling, did you know I've just married another husband?"
"Yes, Daaahling he is number 27. I am such a lucky vooman."
"And Daahling vould you just look at my diamond!"
A new and much appreciated acquaintance has put these thoughts into my head and I am grateful for the opportunity to reminisce a little. So, Dearest, when you read this and suspect that you have provoked it, please do be flattered. Know that I appreciate you and look forward to either developing a lengthy history of acquaintanceship or perhaps, who knows, we may break through the artificiality of the internet and call ourselves friends. Call me whatever you like. I'm happy that you call.