This isn't turning into a thread about stepmums/ mums. I am both a mum. And a stepmum. Where contact takes place every weekend with all children from both ex marriages. For now, that works for the DC's. There may come a time when it doesn't and contact will flex (certainly with my DC's)
I think the challenge with your posts is that it feels like there is a lot of judgement. I don't think you have any concept of what it must be like to be the person who does 90% of the school related stuff. Getting 3 kids up every morning, getting them out the door with the right things they need, ready, clean and dried. That's not forgetting what they may need for extra curricular things like world book day costumes and random mufti days. Then getting them home, getting homework done, showers / mealtimes done. Doing a load of laundry every day.....
I have a nanny to help but ultimately it is my responsibility to check all school bags, every night before I crash out. My responsibility that the house is clean, fully stocked with food....lets not even get onto the emotional challenges DC's have when they are the children of divorce and transitional behaviour to deal with when they come home. Every week.
I don't care if its an amazing stepmum doing all those daily things or a mum. But until you've walked a mile in someones shoes, don't judge.
And yes, to the outside world, when my kids go, I fill my time with seeing friends and doing things. I'm sure it could appear very much as you say, that I prefer going out with my friends. But you know how much it hurts to not see your kids as much as you used to? How much you miss them? Lots. It hurts lots and you miss them lots. So smart people fill that time and try and find a new happy. So that their children are not conflicted when they go. Non smart people don't fill their time and their lives and become obsessed about preventing their children building any form of meaningful relationship with the ex.
Re the shipping off...my time with my kids is less but what they love more than anything is sleepovers with my nephews....so, yes, on my time, they go have sleepovers.
Newsflash; a lot of parenting is about sacrifice, especially when you carry guilt over their lives being ripped apart and living for the rest of their lives between two homes. Most people are simply trying to do the best they can, maybe you should try and see it from that perspective...