<human>: Can you provide a brief overview of the text?

So the basic background is this... My girlfriend and I are both foreigners in the country we live in... I have been planning to go to her country for Christmas, which would be the first time that I meet her friends and family.  I've really been looking forward to this. 

Today she tells me that this other guy she knows will just happen to be in the country over that same time period, and she invited him to Christmas dinner without talking to me about it first.  She says it would just be for Christmas dinner, but I'm worried that this would evolve in to having a spend a lot more time with this guy around as a 3rd wheel... So then the first time I'm meeting all these people in her life it will be in the same context as some other random dude hanging around.  I don't consider this guy a threat, but I do know that he has been interested in her in the past.

Another problem is that we'll be in a LDR for the next few months due to some work assignments, and we'll only be able to see eachother for a limited time, so now I'm in the position of having to share my girlfriend with some guy during the limited time we actually have to see eachother, and have him around during a really important time when I'm trying to make a good impression on her family and friends.  

I really don't know if i'm being unreasonable or not.  If it's just for Christmas dinner, fine, I can live with that, I wouldn't want to be alone for the holidays either... But if this actually turn in to this dude hanging around the whole time, which is my worry, then I'd be really disappointed with the whole situation. I don't know Reddit, please give me some perspective.
<bot>: GF invited some dude to spend time with her family and with me over Christmas without consulting me first, and it makes me uncomfortable.