My wife and I live in separate houses - I live in the countryside and she lives in the city. A couple of years into our marriage I decided to buy a puppy because I always wanted a dog and I have the space and the time now. I brought the dog up, trained him etc. and he’s with me all of the time apart from the odd week when I go on a business trip (2-3 times a year), and then my wife looks after him at her place. My wife loves the dog and indulges him which can sometimes lead to a bit of conflict as I feel she undermines his training. But I’m petty happy to trust her with him and glad they get on so well. So this isn’t the issue.
The issue we had an argument about recently is that she stated he was “our” dog, and I corrected her, insisting he was mine. She got quite upset about that and said because we’re married we share everything, and hence the dog is our dog. I love my dog very much and invested so much time in bringing him up well and looking after him. He has a great, happy life with me in the countryside. I regard him as my dog and I don’t like it that she simply assumes there is this joint responsibility and custodianship. I find it hard to see the issue from her point of view. AIBU?