Bless your co-parent just as they are. Let go of your expectations about co-parenting. Then parent as best you can. Release everyone, even yourself, from the expectations and dreams you had of a wonderful co-parenting relationship.
Two people agree to have kids and a huge shift happens in their lives and their future together. You are committing to a lifetime of connection with this person, even as you are agreeing to bring new dependants onto the planet. It's a massive transition, this becoming a parent. Deciding to divorce your co-parent is another huge shift.
I wonder, someday, will they ask how the divorce happened? Will my adult kids want to know who's idea it was to break up our family? These are conversations I could never have with them unless they asked.
Always treat your co-parent with respect and compassion. A metaphor for co-parenting might be, "Treat them as well as you do a convenience store clerk." You want to get in and get out with as little hassle as possible.