Communication is mainly meant to build bridges by expressing what is going on within oneself. The purpose is to help build a bond of deeper understanding. But if this is not possible or intended then it is best to remain silent, quietly continue doing what you feel is best and ignore the expectations. Silence itself communicates.
If you try to explain them as to why you don’t wish that your child to have much contact with them they will only feel hurt and press you more trying to convince you. Certain misunderstandings are best left for time to heal. Though it may ease out the strain if you tell them that this distancing does not mean that you do not care for them and will not be there when they need you. They deserve this assurance and it will also be a good example for your child to learn. Respect may or may not be there as it is something to be earned but love should always be there as a baseline in life and along with it sympathy and care.
Affectionatley
Alok Da