To call off girl’s holiday on the day?

OP - you come across as being very hard and cold. Lighten up.

Having anxiety is no excuse for sending someone over 100 text messages. That's harassment.

You sounds like a horrible person and a terrible friend.
So just because someone isn’t the same as you and gets anxious about things you think she should crack on because she’s an adult and you can do it so she should be able to?

Anxiety and mental health issues are real and debilitating. Think yourself lucky you don’t have them. Try and find some empathy for other people who aren’t the same as you.

I'd be stern with her.

"Look X, you have sent me over 100 messages this morning. That's just ridiculous and it's getting the holiday off to a bad start. Please stop. We are not going to miss the flight and check in doesn't even open until 1:45. I'll see you at (time and place) as planned. I'm working until 12 so can't reply to any more messages now."

OMG 8 hours 😂😂😂

Stop saying she's an adult!! We get it! You are so much more seasoned traveller than she is. 🙄

This is not looking promising for the rest of the trip. I'm afraid I wouldn't have patience for this hysteria either.

You might have a shock when you reach peri-menopause and anxiety sets in, OP.

This would drive me mad.
Tell her you will meet her at the airport and turn your phone off.

She has no right to spoil your holiday by flapping about the return trip. She chose to come. She knew that would involve two plane trips.

You’re not a nice person OP, maybe you should cancel. It will devastate your friend now, but it will help her later to avoid friends like you. It will give her the chance to make quality friends of value.

Acknowledge her anxiety, give her some reassurance and facts, go on the holiday.

e.g. "I know you're panicking about the timings but don't worry, we'll be fine. I'll leave work bang on 12, be home at 12:15, I'll have a wee and grab my bag (which I've already packed!) then hop in the car. It's only half an hour to the airport so I'll be there by 1pm at the very latest. We've been told to arrive 3 hours before the flight at the very most, so they don't even want us to turn up until 1:45pm at the earliest. I can't leave at 10am as I've not booked it in with work but even if I leave at 12 we've got more than enough time. Like I say, I've already got all my bags packed, we could arrive at 2:30pm and still have more than enough time. I know you're worried but honestly, trust me, we will be totally fine and we'll arrive too early if anything. Really looking forward to this trip! Woop woop!"

You're being a dick. I am sure there are things that you find hard that others don't.

Just tell her you'll meet her there if she wants to go ahead, or travel with you when you go. Then don't engage as you are working.

It doesn't take much to make a journey run askew however, as I'm sure a seasoned traveller such as yourself will know.

and your idea of dealing with it, is to cancel your holiday.

Seems you're both dramatic

She obviously does need that support even if you don't think she does.

If you're her friend offer reassurance and support. Tell her that 3 hours early will be absolutely fine

It really looks like you don't like her or care for her at all

Anxiety is awful, it can affect everything. The least you can do is offer support to your friend.

I would silence the chat (like I do with my husband when he starts to barrage message me) and crack on with what i´m doing. No drama. Do the same.

I feel bad for the friend too….OP is not a great friend to this lady, I am thankful I don’t have friends like OP. It’s okay to be annoyed a little, but to cancel on the day…wow

I had similar with a friend from another city going to the theatre with me. It turned out it was more fear of the unknown. Once I told her how the ticket checks worked (quick scan at the door rather than the long queues she’d been expecting), that the seats were easy to find (tiny theatre) and that DH would drop us off so we wouldn’t need to find a parking space, she calmed down, I knocked an hour of her arrival time and the evening turned out really nice.

over reaction to not go on a holiday as someone has text you - its not a normal reaction

a bit anxious

You call 100 texts, days before going, being "a bit anxious"???

What on earth would your bar be for being actually anxious?!

The friend's behaviour sounds utterly ridiculous

THIS!!

With friends like you, she doesn't need any enemies!

You are completely lacking in any kind of empathy.

Message your annoying friend and tell her you are working and won't be able to read or reply to any messages until you finish at lunchtime. Also, tell her you will meet her at the airport if she needs to get there early.

You sound like a horrible travelling companion. I hesitate to use the word friend here because you are clearly anything but a friend.

You are being so incredibly unreasonable to even consider cancelling. What kind of nasty person does that?

That's quite the empathy bypass you've got.

She's being exceptionally annoying and absolutely ridiculous.

However, I also think it would be ridiculous of you to cancel. She'll probably be fine once you're in your hotel. Just send her one final message: "I've arrived at work now so I'm turning my phone off. I'll see you at the airport at 1." Then turn your phone off and proceed with your plans. Worst case scenario, she continues to be a pain on holiday and you suggest spending some days alone. If she'd really bad on holiday, it might be the end of the friendship, but it will definitely be the end of the friendship if you cancel today. At least if you go, you'll have plenty of anecdotes to laugh about for the next few years. And it might be fine! I don't know, I just can't imagine passing up the opportunity for a holiday in Cape Verde that's already bought and paid for...