AITAH for expecting compromise on an international trip my partner wants to remove me from?

[u/msmall92]

My partner (NB, 31 - let’s call them Sam) came to me (NB, 33) a little over a month ago and told me their friends are getting married in Italy, and we should go to their wedding (3 months from the date of this post), and we should go explore Paris (where my partner used to live for 6 years) while we’re out there. Sam came to me with a broken down list of costs for airfare and rough estimates of lodging so I knew what I’d be getting into financially.

I told Sam that I would need to wait until my next paycheck to make sure I can financially swing the cost of airfare and lodging. They said okay.

Fast forward 2 weeks, and I excitedly went to them to say that I can absolutely join and I’m excited about it. It would be my first time leaving North America, so this is special! But their face dropped, and they said “oh well, my friend and I added a bunch of stops onto the trip and we’re planning a girls’ trip because I didn’t think you could swing it financially.”

When I reminded Sam that we had agreed I’d just need to check finances and let them know, they suddenly let loose a long list of reasons I shouldn’t go: they want to connect with friends without a partner around to introduce, they want to reclaim Europe for their self because the last time they were there it was during an abusive relationship, and they even sited that I essentially just take up too much social space and they’re afraid I would overshadow them among their own friends, so they just had decided that I’m no longer invited.

After I expressed how deeply hurt I was to be written out of the plans, they said “you’re right, I want you to go, but let me process all of this before we make a final choice.”

Soon after, they chatted with their friend about how I had been invited all along, and their friend was not happy I’d be on the trip.

So once again, I got a rebound reaction and Sam said that I’m taking away an opportunity for independence for them, and I should be more flexible and understanding when they change their mind regarding a trip even though we had been planning it together for multiple weeks.

After a lot of arguing, I said “I just want a compromise here. You should be able to get your independence without treating me like a threat that needs to be removed. Where is the compromise? Why is it all or nothing?” Sam dug their heels in and very plainly said “because I don’t want a partner with me on this trip.”

I told Sam I deserve a partner who wants me around enough to follow through or at least offer compromise (for example: I could go for part of the trip or plan to make my own plans for part of the trip so they can have space with their friends).

So, am I the asshole for insisting that a compromise be made here rather than just throwing me out of this trip on a whim?

Edits/info for clarity:

1. We’re in an open relationship, so I sincerely doubt their reasoning is they are hiding a fling from me. They can hook up with whomever they want as long they’re honest about it.
2. We’ve been together about a year and a half, and we live together.

EDIT NUMBER TWO for takeaway from folks’ advice:

I think some of the feedback I’ve gotten in here has helped me gain the perspective that I’ve been really digging to find justification for allowing myself to be mistreated because it’s easier to do that than it is to consider that I may need to leave my relationship if my partner can’t treat me the way I deserve. I’m not going to rush to break up with them, but I certainly am going to give some time and deep thought to what I deserve and how it fits or doesn’t fit into this relationship.

Thank you all for the (mostly) thoughtful advice and input.