Had there not been that mistake

Here I thought I knew it all,
but I had more to expect.
The words left out were what I needed,
but they were words
I should have learned to forget.
Cause when I see the lovely eyes
and
stare into that smile,
I have to remember why I'm here,
at least for a while.
It's easy to think about the happy times,
the sad times and all our exposed fears.
But I've been riding on the thought
that what I remember
isn't what is here.

So when do we let go?
No, not let go and forget,
but let go of the time
we spent thinking on regrets.

Cause each morning I wake
thinking what it'd be like,
had there not been that mistake.