Both G and I have been with both kids every Christmas of their lives. And whether or not that’s a truly important statistic, it feels kind of important. Important enough for us to have made the effort to figure out some strategies that seem pretty sensible. Maybe other dual-households can benefit by hearing how we work it.

Even before we were divorced, there was kind of a division between how G and I celebrated the holiday. Historically, his parents were big on Christmas Eve dinner and he was happy to cook that. We’d all go on our annual visit to the local Unitarian Church, sing Christmas Carols that carefully tried to avoid as much mention of Jesus as possible (I love the Unitarians), and then G would run home to finish dinner while I’d drive around for awhile looking at the lights with the kids. Then we’d come in to a house full of good smells and steaming food and proceed to eat and open some presents.

It’s not that much different living in two houses. I go over there for Christmas Eve dinner, we open presents from each other and from G’s side of the family, and eat ourselves into stupification. Then, depending on where the kids are staying, one or several of us crawls back down to my house, where we reconvene in the morning to open my side of the presents and eat and drink ourselves into an even more advanced state of self-loathing. We follow the traditions of his side of the family most devotedly, mainly because his family traditions include the most drinking and eating.

A couple of our ground rules:

1) Each house can choose exactly how to celebrate its part of the holiday. If one house wants to pick up In N Out burgers and watch Nickelodeon re-runs, that’s absolutely fine.

2) Jill is adamant about keeping all pot luck aspects of the meals out. I personally don’t believe in this as strongly as she does, but we do abide by her wishes. The hosting house is the host; the guest is the guest. I do get that keeping the boundaries clean makes for better role-playing. I walk into the other house not as a former occupant, nor as a helper in the evening’s meal, but as a pure guest, expecting to be able to relax. Which is nice. Really nice.

3) Whatever we decide to do is OK. This year we’re putting on a huge spread, on both sides. Traditional food, big eats. But next year may be different. We don’t want to get stuck in a tradition that confines rather than enhances.

Of course this system only works if you like each other, for starters. And if you live pretty close to each other. If those two things are reasonably within reach, however, I think it works well. The cooking is evenly divided, the kids get to open presents twice, and there’s a kind of glorying in the separateness between the houses. It becomes a movable feast, which is what life should be like every day.

One of the very hardest things Jill and I ever had to negotiate were our “boundaries” — which is rapidly becoming an overused word to define just about everything that annoys us about another person. Boundaries are those indefinable barriers between people that are only visible when they are crossed. If not very carefully navigated, boundaries can rise up and cause hideous navigational snags between people… even people not as intimately awkward — or awkwardly intimate — as a mom and step-mom.

The biggest boundary issue that I inadvertently crossed in the early days was my old house, which was then Jill’s new house. I never stopped by unannounced, but I think my very presence was annoying to her. And — when seen from her point of view — rightfully so. After working my head around it for several years now, I have finally found a place where I can understand. Despite my history with that house, it is her house now. Hers and her husband’s and the kids’. And if I had a new house, I’d want its sanctity respected — as my house — as well.

The house and physical space are painful painful issues. One of those things that come up from nowhere and snap at your heart without notice. One of those things they don’t tell you about in Divorcing for Dummies.

I had purchased that house with the biggest sum of money I had ever saved in my life. Part of those savings had come from a terrible car accident, incurred long before I’d ever met G., that had kept me out of work for a year. By the time the settlement came in, several years after I was able to start working again, I had paid off enough bills from working 50 hour weeks, that the settlement started a great ball of savings rolling. I had put all of those savings happily towards a down payment for the house that I had found for myself and my dewy-eyed new husband.

I had created a home there, worked in it, put floors in it, replanted the garden and tended it through the years of being pregnant, caring for toddlers, and finally finding solace in it when the marriage started to fall apart. And when the marriage was irreparable, I chose to leave the house with my ex-husband without forcing him to buy me out, so my kids would not have to leave the place they were born in. I left it with more grief than I was leaving the marriage, because the house and I had been good friends.

And yet, indeed, I left. And I’ve had to take responsibility for that many times over the years.

I would never have guessed that — among all the other painful issues surrounding the breakup of a marriage — the house issue would continue to be, by far, the most painful. But it is. And it’s one of the things that the person who leaves has to deal with on a more or less ongoing basis, as long as the kids are still living in it.

And it’s all compounded when there’s a new woman living in it. I mean, truly — she can have the guy. That was fine with me. But the house… the house… that is an ache that still isn’t completely healed.

The second I put myself in Jill’s shoes, though, I realized how tricky this whole thing is. I mean, what if I fell in love with a guy who had kids? Who lived in a pretty neat house? Wow, wouldn’t I just DIG going in there and moving in and setting up shop? Of course I would! It’d be really fun and we’d be in love and it’d be great. And there wouldn’t be a moment’s hesitation in digging up the old plants or changing things up a bit. It’d be my guy, my house, and I was now part of it. That is absolutely how it should be.

And it’s simply something I have to get over. If for no other reason than because I would demand the same respect as a person if the shoe were on the other foot.

Where the boundaries get really complicated are when the kids are in the house. I am their mom. And it is Jill’s house. And now it’s suddenly more than me just getting over the fact that my house is now being run by someone else. And it’s about more than her having her sacred space intact. When the kids are part of the mix, where are the boundaries?

I don’t know the answer, but I’ll tell you what my point of view is. Picture a lioness and her cubs. That’s my point of view. If dire need arose and I absolutely had to access the kids — and I couldn’t because I was forbidden to contact them because of the house issue — I guarantee you I’d turn into a snarling hackles-up nerve-endings-tingling ready-to-rumble she-bitch. It’s never officially become an issue — and it’s more a deeply emotional thing than anything else. Now that we’ve worked around our boundaries for a few years and have started trusting each other a bit, I think Jill knows that I won’t start suddenly dropping by for coffee every night after dinner, or arriving unannounced. And I know that if I had to see one of my children, I could. Or call them. Or touch base. If I didn’t know this — I’d go ballistic. Medieval. Sigourney Weaver in Aliens, riding down the elevator.

These are delicate issues. Our lives overlap. And it’s a difficult negotiation. Here are some tips I think we’ve learned about this house and boundary issue:

1) I have to get over my attachment to the house. It is no longer mine; it is theirs. I’m a big girl and made my decisions.

2) I always call well in advance and make sure that my visit is all right with them. I also tell them that it’s really OK to say it isn’t — and I do a reality check with myself to make sure I’m not lying through my teeth.

2) When I go over I abide by their rules, like any other guest. I don’t automatically (any more) go in and start washing the dishes (old habits die hard). And I don’t act like I do at my other girlfriends’ houses, with frequent rummaging through the fridge and peeks into the medicine cabinet. It’s a bit more formal, our relationship. As it should be.

3) Any dealings I have with the kids at the house are purely about the kids, unless something else has been stated or set up in advance. In other words, when I come by to pick them up, I don’t flop down on the couch and expect a cup of tea. In those pickup and drop-off times, I am not a guest. I am the kids’ mom and I’m performing a transport service. They have their life to lead and it’s my job to let them live it.

4) Again, it’s all about communication and being able to see it from the other point of view. When I put myself in her shoes, I could totally understand why Jill was protective of her space. Hell, who wouldn’t be? And what she’s had to do is understand that, for me, it’s about the kids. So she’s had to give up some of her autonomy to enable me to drift in and out of her space from time to time.

Jill can fill her her point of view on all this, but I think of all the awkward intimacies, this one is one of the worst. All I can do, in my deepest dishiest heart of hearts, is hope that I can find a boyfriend some day with a big old house… and an ex-wife who lives (very happily) on the other side of the world.