Sometimes I think things...

Why is it, that no matter where we end up in life, we retreat so willingly into depression?
When we’ve gone beyond a simple want for attention,
and simply want to turn away from the world.
Is it because we truly have good reason to?
It can’t possibly be because it treats us well, or is warm, or comfortable.
Are we just out of energy, in need of a break, so we choose despair?
I suppose it could possibly be that it is familiar, but that doesn’t make sense either.
Why on earth would you want to be familiar with such a thing?
Is there a place for the occasional depression in an otherwise “good” life, or is there something truly wrong with you if you find yourself depressed for more than a few days?
Does it make you a lesser person?
Why do we have so much trouble letting go of it and leaving it behind, if it does nothing but hurt us?
Why do we not flock to happiness and forget all depression in favor of feeling good?
Why do we turn back to depression, as an old friend, the minute the happiness dips below the line?
I’d love a theory
Because at this point,
I don’t have one.
And its kind of irritating,
because I’m looking for answers and I don’t even know what my question is, so in the meanwhile, I ask you this:
Why is it, that no matter where we end up in life, we retreat so willingly into depression?