Douglas Harper's Etymology Dictionary
Wiktionary
a. 1 That loves forever. 2 (non-gloss definition: General intensifier, often with beat.) n. One's wife.
Usage examples of "ever-loving".
Nip and Tuck swing back into Seventh Avenue, and pop into the entrance of a small apartment house, and go tearing up the stairs to the first floor, and when we get there these bloodhounds are scratching vigorously at the door of Apartment B-2, and going woofle-woofle, and we are all greatly excited, indeed, but the door opens, and who is standing there but a doll by the name of Maud Milligan, who is well known to one and all as the ever-loving doll of Big Nig, the crap shooter, who is down in Hot Springs at this time taking the waters, or whatever it is guys take in Hot Springs.
Well, I figure it is a sure thing Miss Kitty Clancy will be surprised to see Big Jule, but I am not so sure about her being glad, because very often when a guy is away from a doll for a year or more, no matter how ever-loving she may be, she may get to thinking of someone else, for this is the way dolls are, whether they live on Eleventh Avenue or over on Park.
It turns out that the proud old Spanish nobleman has white sideburns, and is entitled Conde de Something, so his ever-loving wife is the Condesa, and the son is a very nice-looking quiet young guy any way you take him, who blushes every time anybody looks at him.
Your ever-loving father has never forgiven you, his daughter, much less the Educational Committee, for letting you go on to university instead of the male, his son, your brother.
A royal tiger, the meanest and most powerful carnivore in the entire ever-loving history of creation.