To give and receive advice - the former with freedom, and yet without bitterness, the latter with patience and without irritation - is peculiarly appropriate to geniune friendship.
A friend is Janus-faced: he looks to the past and the future. He is the child of all my foregoing hours, the prophet of those to come, and the harbinger of a greater friend.
I don't think life offers any greater experience than the joyful sense of recognition when one finds in a new acquaintance a real friend, or when an old relationship deepens into friendship, or when one finds an old friendship intact despite the passage of years and many absences.
Friendship makes prosperity brighter, while it lightens adversity by sharing its griefs and anxieties.
[Lat., Secundas res splendidiores facit amicitia, et adversas partiens communicansque leviores.]
A man cannot speak to his son, but as a father; to his wife, but as a husband; to his enemy, but upon terms: whereas a friend may speak, as the case requires, and not as it sorteth with the person.
no person is your friend (or kin) who demands your silence, or denies your right to grow and be perceived as fully blossomed as you were intended. Or who belittles in any fashion the gifts you labor so to bring into the world.
If friends disappoint you over and over, that's in large part your own fault. Once someone has shown a tendency to be self-centered, you need to recognize that and take care of yourself; people aren't going to change simply because you want them to.