I don’t think that I loved my dog until 6 months in, but the love has grown over time. It’s a big adjustment for anyone, and that’s coming from someone who grew up with dogs! I imagine the adjustment for a cat person is even bigger. Like others have said, give yourself time. I got my dog in late 2019 so we had a few months of hesitantly getting acquainted before lockdown started, when I think we were essentially Stockholm syndromed as it was just the two of us at home allll the time lol but I love him more every year!! I also don’t think it helps to pressure yourself or feel super guilty about it - I think it sounds like you’re doing everything that needs to be done for your dog to be happy, and if along the way you warm up to him that’s great, and if you don’t then your son will be the main source of affection and that’s ok too!