[QUOTE=twobits;7910627]
I am finding it interesting so many people are okay with it! I have leased from many different individuals, and three of the five had issues with the “my horse” phrase! I didn’t use it in pictures or public posts, just in person using “my boy” would get me in trouble! The owner expressed that unless I was paying for all of the horse’s expenses then I am not to be using such pronouns. so I changed my phrases from “my boy” to “my favourite boy” because she can’t take away the fact that he was at the time my favourite even if he wasn’t mine.
I think my previous experience with getting in trouble for using such phrases is why I pick up on it now![/QUOTE]
Really? I can’t imagine a normal, well adjusted adult ever calling anyone to task over something so silly. Let alone 3 people. 
ETA: My horse is very social and greets people as they arrive at the barn. He’s made a lot of friends and plenty of people call him “my boy” or “my special boy”. I love it! People are constantly loving on him and checking in on him, so I know I’ll know right away if he’s NQR on a given day. And guess what else. I know that no matter how many people call him “their boy”, I’m going to be the one getting the board, vet and farrier bills. It’s all good.
Maybe the super-possessive insecurity is an age or maturity thing?