I was told to get over it and move on

We had to run to the pet store today because the hamster needed food, and toys. They had some dogs and cats available for adoption. My boy wanted to look at them as most kids do. He laughed and played them. A volunteer asked me if I was looking to adopt because my boy needed a puppy to take care of. I said no, but I'll donate a bag of food for the shelter. She asked why I didn't want to adopt one. I explained I just lost my dog a few months ago and she said well you really should be over that already it's been long enough. You boy is clearly ready. I was taken back by her comment. I wanted to tell her off but I didn't. I just said we'll I'm not over it and we headed over to the small animal section.