I love my child - the fact that they may have some sort of disability or whatever doesn't change that.

She's not saying your child is broken, worthless, whatever. She made an observation that may or may not be accurate. Ignore it or look into it, its up to you.

Taking offense means you think autism is a negative reflection of your child or you. It's not. Children with autism, or any other disability, or other health issue or anything that makes them different from others are still children and we still love them.