To say no, as I was an afterthought

You rarely know which Christmas is a loved one’s last,

As it could be anyone's last this is pointless emotional blackmail

And I would HAVE to ask why I hadn't been included

The answer to that would help make decisions in the future

I agree OP. If you wrote down every single thing in original posts they’d be ten pages long. Plus, the other sibling (who is invited to Xmas dinner) also did not attend wedding

This happened to me and I never really got over it.

People can be busy/thoughtless/forgetful. Maybe there were crossed wires and whoever booked it had understood from someone else that you couldn't go.

I'd try to go. If you don't then you are going to be further separated from your family in the long run

Your mum hasn't forgotten she has three kids, but there are obviously issues with the closeness of your family that have brought this situation about.

It's not like you're all playing happy families and out of the blue one of you has been singled out.

If my family didn't know about a siblings wedding until a few days out, I'd hardly be surprised at the lack of a dinner invite.

YANBU. I would stick to the arrangements with your DH and if your mother asks why just “well you didn’t think of me when you made the decision/booking”

Yes, it could be, but it might just have been organised in a scatty, roundabout way. With your sister abroad, there are fewer opportunities to meet up, so take the opportunity when you can. It sounds like you might benefit from trying to reconnect with your sister. Try not to take offence, over something if it's possible to get the wrong end of the stick over. Reserve that option if/when it becomes really obvious that they're excluding you. Do you have a family whatsapp? If not, I'd set one up and send them all a message saying you'd like to come. If it works, then you haven't lost anything and if it doesn't, then step away.

I'd just be asking why I wasn't invited from the start

It would make me not want to go, because I am very sensitive and feel rejected easily but if there was some sort of reasonable sounding explanation and I was made to feel wanted that might change things

If a half arsed explanation or little regard to my feelings of rejection I would not go, as it would be worse to go and not feel wanted than it would feel just to miss out

Maybe they knew you planned to stay home and that's why you are not invited. Rather than sit and stew in your own resentment, find out the actual reason.

Another who echoes asking why you weren’t included, particularly as it would be your first opportunity to meet your sib’s new wife/husband. Very odd. Surely your mum wants that, particularly as he/she is flying from abroad? Yes, I’d be incredibly hurt.

Op whilst it's hurtful I would take the opportunity to save money and do something really wonderful with your partner. Perhaps upgrade to posh restaurant or buy something special food wise, go to a show... Stay in beautiful b and b etc.

Well say no if you want but also explain why. Otherwise they might be oblivious to your feelings and resentment will continue to grow

If she didn't want you to go she wouldn't have mentioned it though would she. She did invite you as soon as she saw you. Are you normally a close family? I wouldn't give this a second thought tbh but I'm very close to my mum so I'd just put it down to forgetfulness instead of jumping to the reason being her forgetting she had another daughter! If you want to go, just go. You and your DH sitting at home sulking is just pointless

If things are normally harmonious in your family then YANBU. It must be very hurtful. But maybe they have a reason, I would ask. "Mum, I'm really hurt that I wasn't included in the plans for Christmas. Have I done something to upset one of you?"

Don’t cut your nose off to spite your face. If you would like to go, and meet your new bil, etc. then never let inconsiderate people get in your way.

There could be other explanations for this especially if your dm doesn’t have form for this. Sometimes in the early stages of cognitive decline people are so focused on covering up their mistakes that they don’t think through the implications. In DH’s family it would be normal for mil to be the communication hub because she talks to everyone everyday but she’s not always reliable. We’ve all learned to check our sources before falling out!

Even if there is a bit of pettiness going on you don’t have to engage in the game. Pretend not to notice, or just rise above it - it takes the satisfaction out of it.

Have a think about what sort of Christmas you want. If you’re going to end up sitting at home brooding on this (with the best intentions I probably would), then you might be better to take the bulk by the horns and go.

I am really sorry OP ..I would be hurt too and bloody furious in equal measure.

did you not ask why you weren't included from the get go?

It's relevant because if the answer is "we thought you'd be at work/you like to have Christmas on your own/it would be too far to get to the meal" that's a bit different to "we didn't think about asking you, but suppose we might be able to include you if you you want to come".

Surely in this example, once the second sibling invites themselves it’s an obvious time to open it up to the third sibling and chance the booking all at once? Very thoughtless not to.

Honestly, parents can have massive blind spots/ false narratives sometimes. Have you always been the sibling who gets forgotten? Are you the least demanding/dramatic, the one who always got left out, the middle child?

This is exactly the kind of thing my mom would do to me, and then blame me for not being able to go. But she hates me so 🤷‍♀️

Exactly this. I'm sure most bigger families operate like this at times. I might be speaking to my mum about a new restaurant and she'll say oh lets book it and then we'll invite siblings on later. Or some family will be visiting and we'll book a meal with them then put the word out and the booking will be changed to include those who want to come. It's really not a big deal but the fact you seem so disproportionately upset and can't even communicate this to your mum makes me feel there's some strange family dynamics going on

I agree with this.

I'd be very hurt but I'd go anyway. It's your mum who has excluded you, not your siblings and it would be a shame to miss out on seeing them and meeting your new IL just because your mum has done something unpleasant.

It will also give you the opportunity to make it clear that in future you want to be asked about attending family get togethers.

I would try to have a conversation with them about why you were an afterthought rather than cutting off your nose to spite your face. We’ve had this dynamic in our family and since I raised it with my parents they’ve been better about including us.