Who are the architects who stand by their design?

And why can't the heart be a simpler machine?
Why does love remain a mystery?
Dinner conversations after years of getting cold
The things that made us fall in love in houses that we sold
The ghosts of indiscretion pull the rugs from under me
Why does love remain a mystery?
Love is a mystery
Oh oh oh
I never hold you anymore
We are not young like we once were
There is no ruling on the floor
And I don't know you, I am sure
Holding my head and sinking just to figure out
Why I'm adding up apologies, they don't count
And the thing that I don't know makes a fool of me

We cite longevity as the reason we're still here
It's another anniversary, just another day I fear
Since you still hold the girl and I'm the boy we used to be
Maybe we can love, but love is still a mystery
Oh oh, it's a mystery
Love is a mystery
Your love is still a mystery to me