It would depend on what was said and how long I had been seeing her. In your case, I would want to know if she can get past what you had said. I do think it would be hard for anyone, including a therapist, to not react to an attack against their child and grandchild. I have a friend who said the only thing that would ever make her angry with me is if I insulted her grandchild or dog. So to answer your question, it gets back to context and what was said by both of us, as well as the degree of trust that has been built up over time.