I will be in the process of recalibrating my life in relationship to my ex-wife probably for the rest of my life. Even after the kids are off and doing their own lives, there are always collective contributions that need to be made, adult advice that needs to be given, and we will never fully separate from the relationship.
When the other partner decides to ask for divorce there is very little the committed partner can do. The fracture has happened. The other person has declared they are considering divorce. Then that option is forever on the table and could be used as leverage.
Today, at this moment as a divorced father, I know I am not repeating my father's mistakes. My son and daughter hear from me all the time how much I see and love them. I try to meet them on their level, rather than making them adapt to mine.
Down has become the new up, and I have become a new single dad, still committed to his kids, and in many ways, to his ex-wife as well. We are still a family, still connected, even when we're not together.