Made Up W GF - She's Taking Fling Trip W New Guy

My girlfriend and I have a long distance relationship for a couple of years. We been debating for about 6 months whether she would move in with me or move on. She has been a bit off and on the opportunity, and so have I. But basically she was waiting for me, as much as was waiting for her.

Things were getting dicey and we were starting to cool communications. So I booked off time to visit with her and finally invite her to move in and discuss a permanent commitment.

Well, the day before I was to depart, she broke up with me (by email!!) saying she was tired of waiting, and told me she was going leaving town on short trip with a girlfriend. We spoke a few times, re-engaged a bit but I couldn't get anywhere.

So finally I took the initiative and travelled to see her and put it all on the line. She was startled to see me, but flattered and receptive and we decided to give ourselves another chance. We would begin the process of her moving in over the next few months.

Then she informed me that some guy had hit on her during a girls weekend in California a few months back. During our "break -up period" (3 weeks) she booked a long weekend trip to go see him next week. And that she said since she had called him and had already bought a ticket, she was still going!!

She says its just a fling, but I am not sure. I don't have much choice, she is adamant about going, saying we weren't together when she planned it.

She is being honest with me, and she has told me a bit about the guy and confessed some details of how they met, but, of course, I am totally uncomfortable the situation.

What should I do? It doesn't make sense to pull the plug on the whole thing now that we have turned the corner. In a quandry....