Trading a dream for another

They come and they go,
Sometimes they stay,
For a while to gaze a little,
And then go away,
But there is always one of them,
That stays forever with you,
Nursing your sense,
Your comfort through pain,
But then there comes a day,
When you have to let it go,
For another that you love,
You have to sacrifice your love,
And so you come to trade,
A dream for another dream.