I'm in your life for a reason...

i realized at least 20 years ago that i come into some people's life for a reason... and some for a season...
a couple of years ago, a chain email says what i think, and recently it's got circulated again in facebook, and following is the excerpt that echoes my belief (though from the opposite angle)...
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When someone is in your life for a REASON, it is usually to meet a need you have expressed. They have come to assist you through a difficulty, to provide you with guidance and support, to aid you physically, emotionally or spiritually. They may seem like a godsend and they are. They are there for the reason you need them to be. Then, without any wrongdoing on your part or at an inconvenient time, this person will say or do something to bring the relationship to an end. Sometimes they die. Sometimes they walk away. Sometimes they act up and force you to take a stand. What we must realize is that our need has been met, our desire fulfilled, their work is done. The prayer you sent up has been answered and now it is time to move on.

Some people come into your life for a SEASON, because your turn has come to share, grow or learn.They bring you an experience of peace or make you laugh. They may teach you something you have never done. They usually give you an unbelievable amount of joy. Believe it, it is real. But only for a season.