Picking Sides/Opinions?

wanderlustmess
My fiancé (let's call him Kevin) is always picking the side of this other woman. We'll call her Katie. 3.5 months ago Kevin and Katie had sex while we were in an opened relationship. I got jealous after the interaction because it bothered me that they were close friends. She decided she didn't want to talk to him for a while because it was uncomfortable (since she caused a rift in our relationship). A week ago she asked him if he wanted to go see a concert with her put on by their University. He drove 12 hours each way to see her and go to this concert (which he told me was more about getting errands done in our hometown, which he did none of since his last minute plans to do them ie a vet visit, didn't work out). Then he stayed with her the weekend since she couldn't be bothered to find somewhere else to stay. Do I have a right to be jealous here? Are they being shady? She told him she feels like I hate her. He wants me to get to know her because they're close friends. I reached out 3 times and she responded ONCE to the first message. 2 months ago. I tried again this week. She has been online but no response. She told him today it's because she doesn't use messenger often (she has been online since) and said she thinks it would be better if we got to know each other in person. She then invited herself to come visit our apartment this summer. Thoughts?
Picking Sides/Opinions?
5 Opinion