Question: What is the hardest thing about friendship?
Answer: The hardest thing about friendship is annuling ourselves towards the friends against, above our inherently self-serving, self-justifying nature.
Friendship is true only when it’s based on mutual guarantee, where the principle of “love your friends as yourself” is implemented in practice in a way that it actually translates to “love your friend more than yourself”.
Unless these conditions are met we can’t really talk about true friendship, as the connection is still based on egotistic self-interest.