I'm rather stumped on any actual advice to offer here, but wanted to share a few thoughts.

When I had to live with my mother-in-law for a time, I had to send one of my dogs, Cody (RB) to live with someone else for a time because she could only have two dogs in the house and she already had a sheltie named Devon. I chose Cody as the one to live apart rather than Willie because Cody bonded more easily with anyone and everyone, Willie and I were much more inseparable. Anyway, I noticed after awhile that I felt more detached and unenthusiastic with Devon than I usually felt around dogs. Though I did not feel hatred towards him, I definitely had a feeling of "he's not one of mine" and became more easily aggravated with the doggie things he did, like when he chewed up a piece of my clothing, woke me up at 5 a.m. weekend mornings barking wildly at the paper boy, etc.

I explored my feelings of discomfort around him, and came to the conclusion that it was a mixture of things involving the situation that I was somewhat reflecting onto the dog. I think the biggest was that his presence caused me to have to be separated from Cody. The other thing that aggravated it was my mother-in-law, and brothers-in-law when they visited, indulged Devon a lot, letting him do things that my dogs were strictly not allowed to do, such as getting on furniture, etc.

I made an effort to help some of these feelings by taking over Devon's care quite a bit while I was there. I groomed him, walked him, fed him his evening meal. After awhile, I began to feel more maternal feelings towards him, I would get irritated to see people sneaking him treats of people food because he was already overweight. I took on training him better behavior as he was an incessant barker about anything, I started making him sit when ever he cut loose barking crazily. I also threw frisbee for him and worked on teaching him to come more reliably. Like everyone suggested previously, all of this really seemed to help me work through my own particular problem.

I think what this definitely shows though is it isn't just random dislike or hatred for the dog you are feeling, there is a cause that you associate with the dog and so project it onto the dog, without intending to at all of course. You don't WANT to dislike this dog, obviously. The only way I can see you working through it is finding the source, and working through the source. I am not sure how possible this would be for you though.

Have you spoken to your mother about your feelings any, or are you afraid to? If she's the understanding type who would listen to you, I think it could be a very helpful thing bringing this to her to talk about. She knows you personally the way none of us do, so she might have much greater insight to offer you. It really sounds to me like, deep down you want to take her paw when she offers it. It hurts you not to, and it hurts you to see her trying and yet just not feel what you want to feel, but right now there is something walling off your ability to feel and respond the way you normally would with a dog.

I wish I had more to offer you Ky, I truly wish the best for all involved in this situation. I know you must be tormented inside by it all.