I completely understand feeling like you are enabling him, but if he wants to walk away there is really not much you can do about it. Reading your other replies it sounds like you are coming to the same realization, that if you want a break you'll have to turn to other people for support.

Unless you are required to by your custody orders and/or your daughter wants to, I'd stop allowing him to reschedule - if he wants to see her he'll have to learn to make time. I allowed my own ex to reschedule and just pop by spontaneously at first, with my thinking being that he was showing the kids he wanted to spend time with them even if he couldn't follow the calendar. But after a couple months of "dad only wants to see us when he doesn't have anything better to do" or "... when his girlfriend isn't around" I put a stop to that, realizing I was indeed enabling him to continue cancelling. I imagine his thought process being something like: "Why bother taking them for an entire weekend when she'll let me stop by after work one day to drop off souvenirs from my vacation in Hawaii?" Cuz it's absolutely the same thing, right? Give me a break.

It's agonizing, isn't it? I've long since given up any hope of having a weekend to myself - the kids refuse to stay overnight even when he is in town - but I'm still having a hard time accepting that he's destroying his relationship with them and there is nothing I can do about it. I made an appointment with my therapist because I wanted to get to a place where I could be grateful for the time he did take them instead of obsessing over when he flaked off, and she gave me a funny look: "You can't just decide one day to feel differently about something." Bummer.

Anyway, things are finally looking like they are on the right track - both kids are willingly cooperating with the schedule and he hasn't missed a visit in five weeks (a miracle, I know!). I sense another cancellation isn't too far off, though, as his long-distance girlfriend has made the trip for five out of the past six monthly visits - he's overdue for a trip, I reckon. I have no doubt it'll be interesting to see how the kids react.