I have no advice, but I feel exactly as you do.

I have the urge to write a letter too, but what good could it possibly do? On the other hand, how could it hurt any more than it already does?

If WAS's really wanted to come back, nothing in the world would stop them. They really wanted to leave, and nothing could stop them then, right?

We will probably never find out "why?", and we will continue to hurt, and we will continue to hear that we "must move on."

It will matter until it doesn't, and it really sucks.