There is almost a touch of condescension in the act of hiring friends that secretly afflicts them. The injury will come out slowly: A little more honesty, flashes of resentment and envy here and there, and before you know it your friendship fades. The more favors and gifts you supply to revive the friendship, the less gratitude you receive.

you often do not know your friends as well as you imagine. Friends often agree on things in order to avoid an argument. They cover up their unpleasant qualities so as to not offend each other. They laugh extra hard at each other’s jokes. Since honesty rarely strengthens friendship, you may never know how a friend truly feels. Friends will say that they love your poetry, adore your music, envy your taste in clothes — maybe they mean it, often they do not.

Men are more ready to repay an injury than a benefit, because gratitude is a burden and revenge a pleasure. TACITUS, c. A.D. 55-120

Don't flatter yourself that friendship authorizes you to say disagreeable things to your intimates. The nearer you come into relation with a person, the more necessary do tact and courtesy become. Except in cases of necessity, which are rare, leave your friend to learn unpleasant things from his enemies; they are ready enough to tell them.

JUDGMENT Be wary of friends — they will betray you more quickly, for they are easily aroused to envy. They also become spoiled and tyrannical. But hire a former enemy and he will be more loyal than a friend, because he has more to prove. In fact, you have more to fear from friends than from enemies. If you have no enemies, find a way to make them.

The glory of friendship is not the outstretched hand, nor the kindly smile, nor the joy of companionship; it's the spiritual inspiration that comes to one when he discovers that someone else believes in him and is willing to trust him with his friendship.

Don’t flatter yourself that friendship authorizes you to say disagreeable things to your intimates. The nearer you come into relation with a person, the more necessary do tact and courtesy become.

Some friendships are like a marriage, others like an affair; the latter are for pleasure, the former for the abundant success they engender. Few are friends because of you yourself, many of because of your good fortune. A friend's true understanding is worth more than the many good wishes of others. Make friends by choice, then, not by chance.

There’s no such thing as friendship. You just get what you need when you need it as fast as you can. The only reason that people give is so they can take later on.

For not many men . . . can love a friend who fortune prospers without envying; and about the envious brain cold poison clings and doubles all the pain life brings him. His own woundings he must nurse, and feel another's gladness like a curse.

When our friends have deceived us we owe them but indifference to the tokens of their friendship, yet for their misfortunes we always owe them pity.

I have no duty to be anyone's Friend and no man in the world has a duty to be mine. No claims, no shadow of necessity. Friendship is unnecessary, like philosophy, like art, like the universe itself (for God did not need to create). It has no survival value; rather it is one of those things which give value to survival.

Without institutional obligations, the upkeep of friendships require must be very deliberate...

However, the weakness of friendship is also the source of its immeasurable strength. Why do true friendships make us happier than spouses or children? Because they're always a deliberate choice, never an obligation...

Someone does not cease to be your parent, boss, or spouse because you stop liking them. Friendship is more real because either person can walk away at any time. Its fragility proves its purity.

You should never boast of what your friends think of you. That is true testimony which comes from the lips of foes. On the contrary, if a friend speaks in your behalf he will be considered not as a witness but a judge or a partisan.