That's what you and I are on about. Pets are pets, and they can be well loved, but they aren't humans or people.
But not to her.
Because deep down, she wants kids. But society, and feminism, have basically shamed mothers and potential into having as few children as possible, in the name of working for a corporation. Or told them, they can have it all! And that turning out to be a lie, so she has to likely unconsciously settle for a surrogate.
So she puts a lot of effort and misapplied love into what should be a pet/animal companion. And projects all of that maternal instinct onto the dog. That dog is probably more or less treated like a special needs human toddler. And not a pet/animal companion.
This repeats throughout Western society, some of it all over the world. We see it with little girls and their dollies, all the way up to crazy cat ladies. The doll, the pet, the random person, they all get adopted into the position of 'child' in order to fulfill the need to be a mother.
For every single mother who realizes what she wants is a human baby and goes to a fertility clinic, there are probably hundreds if not thousands of women using substitutes like dogs.
Sometimes it's really overt. IIRC Alyssa Milano is on record stating that every time she feels the baby itch she goes and buys a horse.
And, of course, I'm sure that there's an actual psych paper on this. It's probably buried, and the person who wrote it is now a homeless bum after being #MeToo'd.