Is AUTHOR wrong in the post ? POST : Soooooo... a timeline first,

I put my deposit down around september (the start of term) for a ski trip due for the middle of December. This ski trip is for the course I’m on at uni and in my last year of uni I thought it would be nice to go, so me and my housemates have booked on. 

 I remember discussing this with my gf when I put down my deposit, and told her that it would be in the middle of December but was non-specific on the actual dates as I wasn’t 100% sure of them at the time. I’m not sure if she was upset about this at the time as granted I’m not particularly perceptive in general. 

So around two weeks ago it comes up in conversation and I let her know the exact dates leaving and coming back and that my birthday falls on one of the days I’m away. So my gf gets really annoyed at me for this and tells me I should want to spend my birthday with her. I said to her that it’s not about my birthday and I would happily spend time with her for my birthday on another day/weekend. I said that it was more that I really want to go skiing and this trip is the cheapest I can really manage and the only time I can go due to the rigid schedule of placement we have to attend in final year uni (and the fact that it’s a uni trip and I have no control over the dates). I’m not really fussed about my birthday tbh, I never see it as a big deal and don’t like a fuss being made over me, though I understand my gf isn’t like this. She stays angry at me through the next few days, saying it’s not because I’m away on my birthday, but she’s upset because I didn’t check with her before I booked the trip (she did know about it but not the exact dates until 2 weeks ago.)

And now over the weekend I’ve paid the final balance and let her know, then she became really angry with me again. She says it is a lack of communication on my part (which is fine I accept I’m not always amazing at that), and she also says that I should check with her in future before things like this. I personally get the impression she is just unhappy that I’m going full-stop but she says this isn’t the case. 

And now she says she’ll be unhappy about this until I’m back home after the trip (in a month and a halfs time). So I feel horrendously guilty now for booking the trip, and it being on my birthday. In my opinion I’ve not don’t much wrong, I’ve booked on a trip I really wanted to go on in my last year of uni and just so happens it’s on my birthday My gf is really mad at me. I could understand if I was missing her birthday but it’s mine and I’m not bothered about my bday. 

I Dont want to feel guilty for doing something for me. Judge me please internet people, I’m happy to be told I’m wrong