To think of uninviting her

Well that all sounds like petty squabbles. But if you don’t like her just tell her it’s off and give her the money.

Surely this must be new behaviour or you’d not have invited her?

Say "Hi friend - I've been made very aware of your behaviour over the past few days in the run up to our holiday and I have to say it's been very stressful for me. I just don't think going on holiday with you is going to be an option any more so here is the £200 you've spent for the flights and your contribution towards the accommodation. I'm sorry to leave it so late to do this but I really do think it's for the best."
Or something along those lines.

Rather than refunding her, let her go on her own. That way she doesn’t lose the annual leave, and holiday. You don’t have to spend time with her.

Have you told her she needs to rein it in as she’s upsetting you? It would be unfair to go from 0-90.

I think with so little notice you should suck it up and go with her after such a long standing friendship, she might even relax on holiday and be less negative.

If the cost of the flights was cheap I would be inclined to say

"Hi Mabel,

I apologise for this but it isn't going to work for you to stay with us on holiday. Ive found it very difficult maintaining our friendship recently and believe we have grown apart to such a significant extent that spending time together will be extremely stressful and difficult for everyone.

I have refunded the cost of the holiday to your bank account. The flight is still booked and in your name so you are welcome to use it. You can then perhaps use the money I have sent to pay for accommodation elsewhere. I appreciate this is a very last minute decision on my part and I am very much in the wrong for delaying telling you for so long. However I'm afraid you cannot stay with us in Majorca and I no longer want to maintain the friendship.

I hope you manage to find somewhere else to stay. I wish you happiness in life and there are aspects of our friendship I will look back on fondly.

Sorry again.

OP"

You then need to suck it up if she is sat next to you on the flight (although she'd have to have the skin of a rhino to want to do that). TBH it's the least you can do.

It's short notice but better now than having a falling out and trying to go your separate ways while on holiday (which sounds inevitable).

What has caused this sudden decision ? Presumably you must have known her quite well to invite her on holiday with you , especially to share your accommodation. Was she supposed to help with childcare?

I think you might feel worse about this later.

Talk to her - don’t just text her.

If you don't plan ever speaking to her again you can do what you want, so refund the money and tell her why.

But as a pp said, presumably she will have taken leave etc and spent other money in preparation for the holiday so it's a bit cunty to do it with 2 days notice.

Why have you left it so late? A family holiday will have taken a fair run up to get organised so this must be something you have felt only very very recently.

She doesn't sound great, but I suspect this is something you should have done a while ago ( pull a plug on the friendship) and are now panicking because you realise that and are about to act like a bit of a dick.

Being stuck on holiday with someone you're not really getting on with is horrendous. Do what you have to.

There is just no way I would sacrifice my precious annual with my kids on the altar of being nice for someone who is like this.
i had a friend like this and cutting ties was hard. She dialled up over time.
She was jealous of me but also possessive of my time and wanted to be included disproportionately in my life. She was telling me off for not seeing her enough and when I explained how busy I was because of X Y and Z and i explained she saw me more than my own mother.
I was accused of bragging about my great job and told I rub it in her face that I travel for work 😵‍💫

I’d send a message acknowledging how late in the day it is and apologising for that but also saying it’s the best she doesn’t come and refunding the cash.

This. Take some responsibility for not wanting her there. Don’t send some bullshit about doing what you think she does or doesn’t need.

Has something happened that’s making her stressed and negative? Seems odd that a friend of such a long time would suddenly become unbearable for no reason.

I can see why you'd want to cancel her and you probably should but I'm also confused about why it's got so close to the holiday.

Although she'll get her flight/contribution back, she has likely spent on other stuff, planned leave etc so it is pretty mean to cancel her holiday at this stage. How long have you felt like this OP?

This.

Do not sacrifice a holiday for a difficult person.
Her awful behaviour has rightly caused you to rethink.
Do not waste any further time on the relationship.

Demanding difficult people take the chance that they will be cut off by those around them that simply have enough of their bullshit.

That is what is happening here.

Hi friend,

You seem quite irritable recently. I need this to be a relaxing holiday and really don't want things to continue how they've been the last few times we've (meet/been in touch etc). I am wondering if you actually still want to go with us. I'm happy to refund £xx for your booking, or maybe you want to use the flights and find other accommodation. Just let me know by (date).

You've know her a long time, so presumably you knew what she is like?

Why wait until TWO DAYS before?

There must be more to this...

You need to put you and your family first. As long as you realise the friendship will be over just do what you have said. Although I think I would phone her rather than text.

2 days before? I think that's unacceptable.

I would just refund the money. You’ve obviously added her on to your booking hence very little cost. If you don’t want her in your apartment then cancel and refund her costs.

I'n that case I would just rip off the band-aid, refund her money and cut the friendship off rather than endure a week of being stressed out and unhappy only to end the friendship anyway.

Exactly!! What if she's booked time off, bought nee stuff etc 2 days before is tight and it's your own fault really surrkybher being a bitch in the last few days isn't why you want to cut her off you must have known .