I think this has been said before, if her farther only has 4 or 5 hours with your DD he's really doesn't want anything to go wrong, he'll simply not have the time to patch things up, and so wont want to risk being associate with anything negotive over such a short period of time.
It's hard for my kids to adjust to the two different styles of parenting, but I hope they take the positives from both our parenting styles. I like to think that there's some advantage in the same situation being treated differently by the two parents. The easyest example I can think of is when they fall over, my Ex is more wanting to show concern and being helpful, "there, there where does it hurt." Where as I want to foster more independance, "come on stop crying get yourself up.
My expenace is that this can be a positive if both parents support the differences. Or a negative if parents try and undermine each other through these differences.
Also if it makes you feel any better your doing a good job, I DID lose it at my eldest on about the second to last day of a two week holiday (hangs head in shame). 3 DS's 10 11 and 17. It was getting late, but in a hot country so it's much more bearable to go out when the sun is very low. I leave DSs in hotel reception while I go to the toilet, in the time it take to have a leak their's been an almighy bust up, and the youngest has gone back to sulk outside our hotel room. Have a chat with my youngest he tell's me that his eldest brothers are ganging up on him and who pinched who and who didn't scratch who, and how the eldest was making him feel bad.
So the eldest DS1 (17) comes up and I tell him that DS3 (10) is upset can you appolgise for upsetting him, "No I'm not going to, he scrached at DS2 so he's been naughty." Upset DS3 snaps back, "He hit me first." Then DS1 goes, "Yeah but it wasn't very hard, you shouldn't have scrached DS2." At this point I lose the plot, to DS1, "JUST FUCKING APOLOGISE TO DS3." Dead silence ... for a couple of seconds ... Then very sheapish, DS1 "sorry for upsetting you", DS2 "sorry for punching you", DS3 "sorry for scratching you", Dad "sorry for swearing."
Urrgh I feel I've waffled on ...