Happy Father's Day to my daughters' great dad and all the dads around the world. Given that over 50% of marriages end in divorce, one of the most important things we can do as mothers and fathers is to learn to co-parent when we are no longer together as a family. Here is a piece I wrote after a vacation with my daughters and their dad. Happy Father's Day, Michael!

Just like marriage, divorce isn’t easy either, and ours has been no exception. But even though we no longer had a marriage to keep us together, we had something even more powerful — our daughters. And, spurred by our mutual devotion to them, we have made a huge effort to work through all the difficulties and be friends.

This has included spending Christmas Day and both of our girls’ birthdays together as a family every year. And, little by little, with a lot of hard work, we’ve grown closer and closer. Indeed, a couple of years ago, on what would have been our 20th wedding anniversary, a magnificent bouquet of flowers that included twenty yellow roses arrived at my home. The card said, “Happy 20th Anniversary. We’ll always be the parents of two remarkable young women. Love, Michael.”

But this was the first time since our divorce that we had gone on a summer vacation as a family, and this concentrated together time can often prove to be stressful. But we had a fabulous time, hanging out as a foursome, eating breakfast, lunch, and dinner together, and exploring the exquisite beauty of Crete — Kriti to my fellow Greeks. The brilliant sand, the jasmine-filled air, the crystalline sea, the jutting mountains — and history to be found with practically every step you take. Crete was home to the oldest Greek civilization, as well as Ariadne (who helped Theseus slay the Minotaur and then became the bride of Dionysus), and Nikos Kazantzakis (who gave us Zorba the Greek).

What we did more than anything, though, was talking. About anything and everything. We spent a lot of time strolling down Memory Lane, and also taking mental journeys into the future. These future forays were both practical and fanciful (we spent a lot of time the other night, for example, debating the pros and cons of evening weddings and the names of yet-to-be born — and, thankfully, yet-to-be-conceived — children).

The surest sign that my ex and I have reached a better place is a newfound willingness on both our parts to not let our pet peeves get in the way of our having a good time. Even in the happiest of marriages, there are little things that each partner does that inevitably set the other one off. These annoyances are magnified ten-fold when you are no longer together as a couple — which is why making an effort to avoid them is one of the secrets of a good divorce.

For instance, Michael really hates it when we are together and I check my phone or, god forbid, take a call on my cell, especially when we are out eating. He was ahead of me in recognizing how distracting and destructive of all relationships such interruptions are. But even before I had seen the light, I kept to 100 perfect phone ban during all meals. And he didn’t make a big deal of the couple of times I forgot to turn my phone off and it began to ring (especially since I didn’t take the calls)!

For my part, I am really put off by the way he openly fumes if I am even one second late for something. Even on vacation (I always thought not having to adhere to a strict timetable was one of the defining features of a vacation!). This trip was different. When I rolled in a few minutes late to dinner, he wasn’t glaring at his watch. Instead, he would greet me with a warm smile.

It was especially great for the girls to have their parents not only not be on edge with each other, but actually enjoying one another’s company.

Our children, after all, are the most important thing in our lives — and in most parents’ lives, for that matter. It’s a fact that becomes even more inescapable whenever we are in Greece, which is an utterly child-centered society. Children here are treated as little gods, creatures of worship — little totemic beings everyone wants to touch and nurture. They are made to feel so special, with even the tiniest accomplishment cause for exclamations of appreciation and praise.

The fact that Michael and I have these two girls (young women now) together is a bond that transcends all grievances we have had through the years.

And while we did not survive as a couple, at least we’ve survived in the joint parenting of our daughters. We have gotten to the point where there is really nothing left to work out — and it feels completely natural to be able to sit on a beautiful beach or stroll through a museum together.

“God,” Isabella said one night, “it’s hard to remember you guys are divorced.”

For some reason, that made me very, very happy. It felt like I had reached the end of a long and arduous journey. And we were all the better for having made it.

I only hope that, for the sake of the more than a million children a year whose parents get divorced, it’s a journey more and more families take.

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