Dear Tom
I am sorry to hear of that . If I were you , what I would do is Give a call to that friend and ask him for coffee or hang out and explain the misunderstanding face to face . In addition, tell that friend that "I respect the relationship between us very much . I love to keep it forever" .
In future, if some misunderstanding happen between friends , just explain to them immediately.
Your sincerely
LI HUA