To not take step kids on my holiday?

All of this.

Yup… takes them camping because it’s cheap.. bingo. OP wake up. You say you don’t realise things becuse you don’t have children .. have you not got two eyes to see what’s going on.”? It’s classic.

Agree

He is your husband now, but I’m sure he didn’t have a family with his ex thinking that would end. You never know what may happen in life, you could have children, and it could one day be your child being hurt by his actions or lack of communicating.

she kicked off royally, screaming that he neglected them, spent all his money on himself and nothing on them, and that they should have come in the trip.
That obviously was never going to happen

Why post in AIBU about whether you should have taken the dc if you feel it is "obvious" that you wouldn't?

To hear people slagging off his ex? Or rage bait?

Because you sound very cool, calm and opiniated and collected about the fact the ex is "obviously" in the wrong to challenge the situation, so I am not sure what you are asking?

All sounds quite secretive. It seems strange that if their Dad wasn’t going to be seeing them that he wouldn’t communicate with them why and where he was. A lot of this post mentions the ex but what about how his children feel about the trip. Sounds like a lack of communication and upset caused because of a failure to communicate. All avoidable

There are lots of comments that sound suspiciously inflammatory - like the family who earn millions and millions (I mean who really says that?!) and are very nice but still not nice enough that the dc of her partner might visit with their dad because it's such a very "distant relationship."

It's incredible how on these SM threads the ex/bio mum is always a screaming crazy woman. 🙄

Different perspective here.

My ex was super-keen to rush his new partner into a replacement mum role. Literally the first weekend she spent with the kids she was in the house at breakfast time when they arrived and was making home-made pizzas (family tradition with me from when they were young) with them for dinner time.

Since then my partner has started palming off the kids to her when they’re sick instead of taking leave himself (easy to do as she works for him) and getting her involved with buying our tween girl’s first bras, which DD found completely mortifying.

Ex only has the kids two weekends a month so the kids’ relationship with him isn’t particularly close. They are teens/tweens and neither of them are interested in having a relative stranger act like their new “bonus mum” when they’re happy with the mum they already have. What they would really like is a dad who engages more with them during his already-minimal parenting time.

As their mum I also don’t particularly want their dad’s girlfriend setting herself up as an unrequested extra “parent”, trying to outdo me with expensive presents and chipping in with opinions about how my kids should be parented.

I would respect her a lot more if she stuck to just being pleasant to my kids and supporting my ex by being a partner in the things they share together (finances, housework, emotional support, work, etc) rather than enabling his slack parenting by covering his responsibilities for him. From my point of view (and as my kids are old enough to have their own opinions, from their point of view too) they’re not her kids and she doesn’t need to act like they are.

I’m not sure this is real, it is getting more selfish the more I read. The issue isn’t where you went op it’s the 3 weeks without his children. He did not bother to tell them just got his sister to collect them. How are they supposed to feel secure if they don’t know if he is in the country or not. He needs to start treating his children equally and taking them on decent holidays that don’t always involve a tent.

In nuclear families it's pretty common for parents to take a trip without their kids. No issue there.

It's pretty uncommon for it to to be for three weeks, and for a parent to take that much annual leave that isn't used to spend time with children when they're on school holidays.

Rage bait crossed my mind: look how she has capitalised the "MY family's holiday."

So yes, he pays his ex CMS and nothing more?

I don’t understand, if he longs to see more of his kids, why use 3 weeks of annual leave without them, that’s going to reduce how much he can see them the rest of the year surely?

Why would he miss a precious weekend if he’s so sad about how little he sees them?

Why wouldn’t he tell them, and just let them be picked up by his sister?

Doesn’t add up. Reality is, he just isn’t that bothered about his kids OP. He isn’t acting like someone who really cares about them. At all. The fact that you didn’t even consider that they might be disappointed not to see him - which means he hadn’t raised that as an issue - says a lot.

I agree with you about that. In my post above I mentioned it.

"If I could offer one very gentle piece of feedback: "They found out on the day when they were supposed to go to him. Instead of him, his sister came to collect them." I completely understand that you likely didn't want to alert their mum to avoid a difficult reaction, which is so stressful. However, in hindsight, it might have been a bit easier on the children if they had known the plan in advance."

I genuinely don’t understand women who get into relationships with men who have children & then don’t treat them as family or even get to know them/spend time with them.

It’s kind of evil.

then you will have children & the my family and his children with someone else will become more prevalent.

I guess you can’t put yourself in the shoes of the ex & the children & how it would feel if it was happening to you.

plus what a great man you have, prepared to drop his kids for you 😃. Whats that munsnet saying a prince amongst men

The issue to me is that he didn't tell his children he was going away for three weeks but just sent a relative to collect them on the weekend they thought they were spending with their dad. I'm struggling to see how anyone thinks that is anyway acceptable parenting.

There are reasons (or in your words - excuses) for their actions and I’ve stated them
In that case, the ex's reasons for expressing herself on the matter was hearing how upset the children were at their dad acting like a selfish twat.

Sure:

1. that he went for 3 weeks (I don’t know any parent that does that)
2. that the holiday wasn’t a gift, he paid for flights himself, they just paid for events out there (I don’t know any parent that does that whilst the only holiday they’ve ever taken their children on is camping in the uk)
3. that he didn’t tell his children he was going, nor where he was
4. that having not seen his children for near on a month, and not bothered to tell them where he was, or communicate with them at all throughout the trip, he found it strange that they weren’t excited for him when he showed off his photos
5. that he has no relationship with his children as he only sees them (if he’s not on holiday) twice a month

What could she have done to affect the trip though? Her control tactic seems to be getting the kids to miss plans with the father, causing him to lose out on the cost of the kids’ tickets. In this instance, he wasn’t taking the kids, so nothing to lose out on.

Edit: sorry, on re-reading I realise I misunderstood your post. Yes, she might have refused to agree to an international trip but given enough notice the OP could fight that. I guess my response above applies more to the OP, as I’m struggling to understand why they left it so late to inform the mother of their trip.

Of course yanbu. You were invited to visit YOUR family abroad, and your DH was invited along. Its nothing whatsoever to do with his children. He probably shouldn't have mentioned it to his kids but the ex is bang out of order booting off about it.
If there is a next time tell him to keep schtum

about it

Actually I did read all the OP's posts. I must have missed something though. Please let me know what it was.

^ this ^

Considering all that OP has said about the children’s mum withholding contact, does anyone think it would have been even a possibility that she would have agreed with a 3week trip international trip without her?

OP, please ignore the negative comments. It is perfectly reasonable for you and your DH to visit your family without your stepkids. It’s nice that your DH gets holiday time alone with his DC —it’s a chance for them to bond with just their dad.

If I could offer one very gentle piece of feedback: "They found out on the day when they were supposed to go to him. Instead of him, his sister came to collect them."
I completely understand that you likely didn't want to alert their mum to avoid a difficult reaction, which is so stressful. However, in hindsight, it might have been a bit easier on the children if they had known the plan in advance.

Sending you lots of support!