There's an old parable from the east. It's daoist, or buddhist, or something, and I'm sure i'll butcher it, but it serves to illustrate my point:
A mouse is running from a lion. As he runs, he fails to see the cliff up ahead. He tumbles over the cliff, only to grasp a strawberry vine hanging from the side of the cliff. As he hangs on, he sees tigers below, waiting for a tasty morsel to drop. He looks at the vine, which is slowly being pulled from the cliff by his added weight, and at the end of the vine, on which there is a juicy, ripe strawberry. He plucks the stawberry from the vine, smiles, and comments: "How sweet it is!"
The whole moral is to appreciate the gifts and joys of the present, and not to worry for the past or the future. "Live in the now" would sum it up, and the eastern concept of "being present" explains it as well.
The past and the future are concepts over which we hold very little control. We cannot change the past, and we cannot predict the future. All we can control is the present, and how we act and interact within it.
Jilluser asked the question about the "perfect" life, based on a number of blogs offering advice as to how to achieve it. The question she asked is whether there is such a thing as "perfect". I believe that "perfect" is a state of contentment with the state of things as they are, and an inner peace that cannot be shaken by external factors.
And so, for the moment, I believe my life to be "perfect". Ask me in five minutes, and you MIGHT get a different answer. But, NOW is what matters.