That One Friend Quotes by Aristotle, Douglas Pagels, Henry Adams, Solomon, A. A. Milne, Erica Jong and many others.

Without friends no one would choose to live, though he had all other goods.
A friend is one of the nicest things you can have, and one of the best things you can be.
One friend in a life-time is much; two are many; three are hardly possible. Friendship needs a certain parallelism of life, a community of thought, a rivalry of aim.
Two are better than one,because they have a good reward for their labor. For if they fall, the one will lif’ up his fellow, but woe to him that is alone when he falleth, for he hath not another to help him up.
If you live to be a hundred, I want to live to be a hundred minus one day so I never have to live without you.
Sometimes it was worth all the disadvantages of marriage just to have that: one friend in an indifferent world.
Friendship is one mind in two bodies.
The antidote for fifty enemies is one friend.
I desire so to conduct the affairs of this administration that if at the end… I have lost every other friend on earth, I shall at least have one friend left, and that friend shall be down inside of me.
When you’re scrambling to fill the void in your life and you feel like you’re drowning… we all yearn to hear that one friend’s voice, say: “You’re going to get through this.”
Friendship is unnecessary, like philosophy, like art… It has no survival value; rather it is one of those things that give value to survival.
One of the surest evidences of friendship that one individual can display to another is telling him gently of a fault. If any other can excel it, it is listening to such a disclosure with gratitude, and amending the error.
There is one friend in the life of each of us who seems not a separate person, however dear and beloved, but an expansion, an interpretation, of one’s self, the very meaning of one’s soul.
He who has one enemy shall meet him everywhere.
A friend is someone who knows the song in your heart, and can sing it back to you when you have forgotten the words.
Blessed are they who have the gift of making friends, for it is one of God’s best gifts. It involves many things, but above all, the power of going out of one’s self, and appreciating whatever is noble and loving in another.
The best mirror is an old friend.