As the title says. I am using a throwaway account because my main is known and I want to give as little personal information as possible. And I'll try to keep this as short as possible.

So one of my (28F) friends (29F) is turning 30 this year and always planned to go on a trip to celebrate her birthday. While this has been very clear for at least a year now, the question for me was whether it would be doable or not depending on destination and current situation.

To summarize: we live in a European country and have different lives. Her dream is to visit as many countries as possible, which I think is great. For me it's difficult because I changed my career 2 and a half years ago so currently I'm a full time student with a small job on the side. In my case money is always tight because I try to manage it carefully and there have been many difficult circumstances throughout the years, so it's something that's known to all my friends. Also important to mention is that my friend is an extremely extroverted/social person, that type of person who is instantly friends with anyone she meets, so she knows people seemingly all over the world and is always traveling everywhere to visit them/attend weddings/birthdays, etc. This will be important for later.

Last year she said she would love to visit South East Asia for her birthday and I told her I'd like to celebrate with her but didn't make it clear enough that I couldn't make the promise to have such a big trip, at least as I recall that conversation . It sounded like a fun idea at the time. I think she has always thought it could be difficult for me to attend her birthday because of money.

Eventually she realized that her first option would be too far away for most people, considering vacations days and prices. However, she said she would definitely not celebrate in Europe and that was that...so her next idea was to travel through Africa. Her plan is now to arrive to a Northern African country (not that far away by plane from Europe) a few days before her birthday, spend some days at the beach and then fly alone to explore the continent further, so essentially only spending around 3 days with friends.

Now.. I am not going to lie, I wasn't eager to hear about the final destination. Of course I was happy for her to keep exploring the world but I do not have this country on my list of priorities (nothing personal) as I limit my traveling budget and prioritize places I want to see first and foremost. Of course it is her birthday and essentially of her own choosing, and I said I would love to celebrate together (I didn't really think about the implications only that it was obvious it would be a nice time with friends) but now I am doubtful. In March after she chose the country, I told her I needed to wait until work started in April again before deciding when to take vacation days and talking to my boss about it, but the more I thought about the trip the less I was eager to travel. Because I do not have many free days as I only work minimum wage I have to choose my vacation days carefully and would only take 2 at the most for this trip. Seeing how expensive the plane tickets are (200-300 € to spend max 3 full days there and although she said she would pay for the accomodation) I decided it was way too much for such a small trip. I would rather spend money to have a nice celebration/surprise party and maybe have some interactive present for her when she comes back. I considered this also because I know a few of her closest friends are not going either.

In this case, the money is the main of my problems because my scholarship ends in September and there are some other things I need to consider at the end of this year/beginning of the next so I want to save as much as I can. Even though I knew she wanted to celebrate outside Europe and would be glad to go, now as the prices are increasing and some other logistics have been changed by her, I am doubtful about going but more so about the reasons and the current status of the celebration. Currently I know of only one of our friends who has bought the plane tickets and because the direct flights were too expensive, he booked some days in the south of France to take a small vacation on his own before flying to where my friend wants to celebrate. But that is not doable for me.

A few weeks ago I had a phone call with her and she explained to me that very few people are coming but she is fine with it. In that phone call she said she understands if some people can't go (like students) and that she had to accept it if she ended up celebrating alone. But the further we talked about it the more I realized she wasn't fine and was pretty upset and very bothered that it is not working out (which is understandable). However, what bugged me was that she was mad at one of her closest friends because she had already been to that country some years ago and didn't particularly like it. My friend could absolutely not comprehend why this was a thing: she weirdly kept on insisting to me that if money is a reason not to go she can accept that, but this friend in particular has "no valid reason not to go, she has the money and can take the vacation days" (to quote my friend). And this is where she dropped the argument of her always being available for everyone at any time, she (over)books every weekend with small/medium trips or visits with friends because she wants to spend time with them and she expects her friends to give back this one time for her big party celebration. I understand her point but I think it's not easy for everyone to go to another continent only for a birthday party and it's not fair to only accept "very good reasons" for them not to go.

As I write these it may sound very obvious but considering that such a small amount of people are going and somehow everyone expects me to because she considers me her best friend, I have had trouble seeing this from an objective perspective. Would I be the asshole not to go? Even though of course money is the main problem, the destination, the small amount of time and honestly that she prioritizes travelling over actually spending quality time with one the friend who already bought the plane tickets bugs me (essentially, he booked a more expensive flight the day after her birthday to fully enjoy that day together and sleep in a little bit but my friend still booked the flight to her next destination the same day of her birthday in the evening because it was cheaper).

I am going to tell her this week that I won't be coming and although she weirdly reminded me many times that said she would understand, I know she will be very disappointed with this. And for the sake of keeping this short, it would open a can of worms between us because some things have not been working out for a while... another reason I am not super eager to go. So would I be the asshole to not go to the celebration party?

I would love to receive some insight from outsiders. I know this is not the biggest puzzle to solve but to me it's somehow difficult because of social conventions and because I know she would hate to spend her birthday mostly alone. But at the same time... It was her plan all along. So.. WIBTA?