To tell my mum I’m not taking her on holiday again?

Totally understand why you would feel like this but I'd give you mum a chance and explain to her everything you have just said here.
Including son.

She geuninly may not realise and also she maybe desperate for care, extra care having that other person around gives.

After that decide and set firm boundsires.

Agree it just sounds like a clash of expectations. These things happen sometimes in multi household holidays. Wouldn't have killed the 18 year old to go to the bar for her or check the menus either, if she really couldn't do those things herself.

If you want to go away with her again, I agree with the PPs who've said a weekend just the two of you makes more sense. And have some discussions about what's expected beforehand. In particular I'd want to be clear that she's aware she'll need to do the things she's capable of doing. For example you mention her wanting you to sort her medication. Does she not do that herself at home?

If she has mobility issues then you can’t really leave her alone. You should have thought it through before inviting her. I think you were just frustrated at spending all your time with her and missing out on the kids. I think perhaps go away for a few days with her one to one, and save your big holiday with your husband and children. I think it was too much responsibility for you and meant your husband was flying solo for most of the holiday with the kids. I do get it as my father is blind with Mobility issues and can’t be left alone somewhere that’s not his home. It’s draining being a carer and does take your time away from your family. 🌺

Considering she is able, I think your mum has over relied on you during the holiday, but I don't think she's unreasonable to imagine she'd be included in your day-to-day activities within her capacity, of course; otherwise, what's the point of her being on holiday with her family.

I don't think you can tell her you won't be holidaying together again, based on her expectations. But I'm not sure how you do tell her that she won't be joing you again. Not an easy one.

I can’t see why you need to announce it, just don’t take her again. Doesn’t sound like she’s enjoyed it either so she may not even want to come again. Being able to manage on her own in her own home and routines is different to a pool side holiday though and I think it’s understandable she needs a bit of extra help. Yourmother isn’t to blame for your behaviour though, shouting at everyone and being so moody that it’s upsetting your kids is on you. I think your mum sounds like she’s been far needier than necessary but I think there is wrong on both sides here and I agree this holiday is better as a one off.

I am not far off your mum’s age, significant health issues.
The last thing I would want is anyone on a holiday having to ‘sit’ with me while there are other things to do, especially with kids involved.
Yes, it’s a bit shit when your body won’t do what it used to but you must accept it and work with it.
So for me I’d be sitting by a pool with my Kindle. iPad in my room for a few films. Some family time at meal times, and then maybe a few hours here and there where someone might spend time with me.
What I wouldn’t do is emotionally blackmail a loved one it’s not fair, especially on a holiday.
If she can organise her meds at home, she can do it on holiday.
I am not being cruel, in fact I totally get where your mum is at physically.
It is not just about the holiday. If she’s behaving like this now at 63 she could be around another 20 years and her demands will increase when they don’t always need to.

No need for any announcement, just don't ask again. A weekend away with just the two of you might be something to consider in future, not the traditional week in a resort.

You all are staying in one room??

I seem to have spent the week looking after mum. she wants me to go everywhere with her, carry things, get her drinks, help her getting changed for the pool, sort her medication and check menus for her.

This sounds tough on you and of course Yanbu as this is your holiday too.

on the fourth night she told another couple at dinner “I don’t know why she’s brought me if she’s going to leave me on my own all the time.” I spoke to her and she said I promised her a holiday and have barely spent any time with her. but I’ve spent nearly every evening sitting with her instead.

This suggests you have left her alone all day and just spent evenings with her ?

my 18 year old said that he doesn’t want grandma coming on holiday again because “she makes you miserable and then you shout at everyone

Why are you shouting at everyone?

As someone who includes elderly parents in family holidays, it's a great opportunity to spend time together but you can't treat it as a normal family holiday, dealing with intergenerational needs is tricky and it looks like this hasn't been considered. Can you not adapt some of your daytime activities to include your mum but if she has come away and spent the first 4 days waiting for you to return from the beach or activities, it's unsurprisingly she is not enjoying and it's not working.

I don’t see why you need to make a bug announcement - if you don’t want to go on holiday again with your DM, then don’t. When you say “doing some things together and some apart” - what exactly did you have in mind? As far as the beach is concerned, did your DM not want to go, or did you not want her to go? If one of your DC is 18, did they not want to do things on their own sometimes? It’s difficult because your DM is on her own - she probably expected to be included in “family” activities. It’s not reasonable of her, though, to prevent you from doing things with your DC because she neither wants to take part in the activity, nor be left on her own.

I'd be the granny in this situation. And there is NO way I'd want to be with family for every minute of a holiday! I'd actively be wanting time on my own. A book. Scrolling on my phone. Relaxing (napping) in the sun. And I'd also realise expecting my DC to spend time with me exclusively and restricting what the children could do because of it was unfair.

Do a separate weekend just you and her next time.

I agree with this 100%.
You don't have to make an announcement.
Just don't arrange another family holiday together and if she mentions anything just say the 1st time around wasn't a good experience.
Your mom does appear to be lonely so maybe arranging some days out with just you and your mom could bea better idea rather than a holiday away.

Why couldn't she go to the beach too? If it was meant to be a family holiday I would expect you all to stay together, of course you your partner and the kids might go in the sea and she might prefer to stay on a lounger on the beach, but all of you in the same place. And why couldn't you all be together in the evenings?

I agree that there’s no need for a big announcement, just don’t do it again.

Whatever the circumstances, your mum backchatting about the holiday and dissing you to some randoms she met is not on.

I would think tbh that your mum is naturally a bit of a whinger and the grass is always greener, but she doesn’t expect to be taken at her word, she just likes creating a situation where the person she talks to feels they should do something. Tbh if she ‘always wanted to see the kids on a real holiday’ she would have made it happen by now - nothing was stopping her booking something herself years ago. Your eldest is 18! I’d say stop taking everything she says at face value.

Likewise, really listen to what your eldest said to you. Your reaction has made the holiday less fun for them. Have a think about how you react to your mum and perhaps other situations too. I always recommend therapy because it’s done so much for me, but a bit of thinking about what you really want and your relationship with your mum wouldn’t go amiss.

Has to be 8.

I think you're actually strengthening OP's mum point here...

Your husband was poorly and you said "we" stayed behind. You stayed with him.

"my 18 year old said that he doesn’t want grandma coming on holiday again" - what have I just read?

Or has she subsided you?
I think the main issue though was that you both had different expectations from the holiday and so your experiences have been different. I think you are both right because you have both been disappointed but also both wrong to just assume what the holiday would be like.
You are not unreasonable not to do it again though if you don't want to

Your mum holidaying with your family hasn't really worked out and that is ok. You know now it doesn't work.

Perhaps sometime you and her can go somewhere together as she seems to want you all to herself. Better to do that separate from your family holiday.

You don’t need to say anything, just don’t book with her again.

Definitely don’t go away with her again. You might just be better off never telling her about where you’re going on holiday again. Don’t tell her about dates or where you’re going or anything.

She decided you would be her companion, that’s not a holiday for you.

Mobility issues aside, your mum is younger than me, and I wouldn't behave like that! In fact, I would enjoy having quality time on my own in the peace and quiet sometimes, away from the hurly-burly of a family holiday.