We talk about that alot on here...very commonly it is mourning the dream which has no real bearing in reality.
Being happy in reality is what matters...who wants to sacrifice their one and only life to an appearance and daydream? That's not living. It's existing.
You are just acknowledging the truth. Saying it or not doesn't change it at all.
He knows all the work you've done on the marriage..it has kept you busy..while he hasn't been in the marriage responsibly.
No, it isn't fair to the family.
But you haven't been able to change or fix it.
Because it takes two.
I do suggest a consultation with an attorney before you say anything, but this is your life and you do what you can live with..it's the only way to live..