Friendship is brittle and strong at the same time. It can bring out the best and worst in you. It is capable of making you soar or dive. It is nice, in appropriate doses, and horrible, when too little or too much.
Friendship should strengthen you. Yet you shouldn't rely on it all the time.
Friendship should make you happy. When your friends make you cry all the time, ditch them.
Friendship is like holding hands with someone, for better or worse, never letting go.
Friendship is conversing without words. Sometimes, you don't need to ask. You just give and offer consolation, when the time is right.
Friendship is caring and loving and sharing.
Friendship takes efforts. From time to time, contacts must be maintained.
Friendship can be peculiar. When someone, our of the blue, says "hi" and you know you can talk to him/her without reservations, you know that (s)he is a friend.
Friendship cannot be forced. Sometimes you click, sometimes you don't. Sometimes it takes minutes, many times, it takes years.
And sometimes... your greatest friends are cats. Or dogs. Or people that you only meet once, that brings profound changes in you.