“Dear Parents:
I appreciate your concern about what might seem like a lack of friends to you.
However, I am more than capable of making my own friends should I want to. When I chose to have friends, you will know that after the fact, not before. You may or may not like them. That is your prerogative.
What isn’t is your attempt to make me have friends when I show no interest in doing so.
I love you and respect you. Please show me the same by honoring my decisions, even if they include not making any friends at all. Should I want your perspective on how you made friends or how you maintained friendships, I will ask you.
Sincerely,
Your independent son/daughter/offspring”