You are not alone. I think this relates to a common parental feeling. Many parents want their children to take after them. This often manifests itself in wanting their children to take up the family trade, for instance. What conflict often arises when the child strikes out in a different direction, causing "disappointment" in the parents. Yet isn't it valid for the child to make their own choices in life? Of course it is!
The same thing happens with religion. Pity the child of Muslim parents who informs them that they are changing religions. Or the child of Jewish parents who tells them the same thing. What disappointment this causes! Yet isn't it valid for the child to make their own choices in life? Of course it is!
So even though it hurts to hear this from a parent, since we are hard-wired to want to please our parents, sometimes in life you have to make your own choices. The wise parent will recognize this and, even if disappointed, give their blessing and support. JW parents don't get that option, for they are propagandized into believing that you will die for your choice, and soon. It is not surprising to hear these words from a JW parent, therefore. They have the natural parental desire to see their children take after them, and they have the further JW imperative to show disapproval of anyone who leaves. How could they NOT express disappointment?
They try to make it personal, but on a certain level, it really isn't. It's almost universal among JW parents. You are not alone.