A prayer that you will find peace quickly with this. Even with a congenial divorce, I can still find regrets and frustration with leaving behind so many years.
As mentioned above, get a lawyer ASAP. Make him/her your confidant. They’ve been through most scenarios and can give you a good idea of what to expect and what to watch out for.
You just mentioned that you expressed your expectations. Realize that anything you talk about can reset the “negotiations”. I was able to deal with my ex because we agreed that it was 50/50 for us. I would guess from the unexpected departure, your wife won’t be as forthcoming as amenable.
Boy! The kids thing! Always remember that they are keeping track of their parents and what they do and say. In my case, my son told his mom ‘adios’ as she “abandoned” him in pursuit of her next husband. I doubt he ever trusts her again.
Learn to like ad be yourself again. Happiness is within you. Something to share with someone in life- not find in someone. Your love is a gift as is the love someone will give you. You will find another, just be open to trusting again. I was one of the lucky ones to find another that has been a blessing for my son and me.
Best of luck to you, Brother!