<human>: Give me a shortened version of the text

Hey,

so my girlfriend (we do not live together) yesterday while we were having dinner mentioned she may be going to another country for a festival in two weeks. She will be there for the weekend. I asked her a few times whether she is going alone, she said yes. Asked her if she wants me to go with her, she said no. But then she mentioned she will be meeting someone there and maybe her brother (if he can make it over there). I asked who that other person is and it turns out it is her ex(who lives there) from 3 years ago. They have been friends for a long time before dating. I told her that it is very weird the way I find out about that. I had to ask her so many questions to find out. If she'd been upfront with me, it would have been much better. 

I then asked about him and their relationship and I said that I cannot stop her and if she wants to go she can go, but it makes me a bit uncomfortable. He also lives nearby in a big house. I asked her if he invited her over to stay with him. She said not, but it will probably happen. She asked if I will be okay with her staying with him, as he lives nearby, she knows his parents (they have been friends for a long time and they keep sending her stuff for christmas etc. ). They live in a huge house and at the moment I thought, if it is easier for her, it will not be such a big deal.

Today i wake up and think I made a big mistake giving her so many green lights to do whatever she wants. I feel so iffy about that situation and how she decided to put me through this. I would never ever do this to her. 

I am a bit confused and am thinking we should have a talk about that today. What do you think? Should I be ok with this? I do trust her, but the way this situation came about is making me uneasy.
<bot>: Girlfriend wants to go to a festival for the weekend with her ex and possibly stay over at his plce. I said i am ok with it, but now I think I changed my mind.