Stop explaining then. If they really care about you, will come around sooner or later. You have to understand one thing, what people say about is none of your business. Don't let it ruin your peace of mind. Enjoy your own company. Be a good sibling and try to avoid arguments. Just smile :) and say okay.
Have you tried talking to your sibling about how you both can work on the relationship to strengthen the bond and then communicate with each other.