GF (F24) planned vacation without me (M25)

My (M25) girlfriend (F25) and I began planning a winter vacation to the Rocky Mountains to spend a week in January together in the snow. She typically leads trip planning because I'm just happy to come along and genuinely don't have much opinion on WHAT we do. But she has voiced that she wants me to take a more active part, so for this trip I did try to take a more active interest in the details.

Then her and an old friend of hers (M23-26ish) reconnected after he broke up with his girlfriend and they began messaging everyday as opposed to occasionally every couple of weeks. I do genuinely believe it's just platonic and I have no (actionable) concerns there. However, the trip plan abruptly changed from her and I spending the week in a cabin to the 3 of us going to Pennsylvania to help her friend move and look for a house. Again, I go with the flow, so it is what it is. My GF starts talking about how she instead needs to go visit her family in the southwest on her own to address some family business instead of either trip that was planned. I just go with it and tell her I'm down for whatever she feels is best and that I can go help her with her family if she would like, but regardless of where we go, I need time in advance to schedule time off at work and she needs to decide where we (or she) is going this winter. She tells me she is waiting on her friend to give her his available days and we can make a plan from there.

THE NEXT THING I HEAR OF IT is when she asked me if I was off 2 certain days to drop her off and pick her up from the airport and that she is going to Pennsylvania for a week (presumably with her friend). She used singular pronouns and emphasized that I would only be picking her up and dropping her off at the airport. She made no hint that I was at all invited to come and I feel like I would be insulting myself by asking to come where I'm obviously not wanted.

Her and I have been stressed from work and each other and have fighting a lot in recent months, so this act of distancing isn't surprising but it definitely is baffling and hurtfull how casual she has been about her decision.

I don't know if I should confront her before the trip or wait until after so she can at least have a good vacation or if I should just desensitize from it and let it go?

TLDR: GF cancels romantic vacation in the mountains to visit her freshly reconnected friend without me and asked me to take her to the airport.