Things going well so far
We were able to get together last night and have diner and talk over everything that happened in their conversation. It was a good talk they had where he was angry enough to actually vent about how he was feeling instead of continuing to keep it to himself and leaving her confused.
Essentially he said he felt the relationship failing for years and it had changed this year to where he was no longer sure he wanted to be in it. Since my arrival he saw that she was very different when she was with me, happy. At first he was happy for her. Then he started feeling like they were fighting more often as she was not backing down as easily when they did fight. He said that he felt he was losing his partner and it stressed him to see her interacting with me and being happy.
So I'm not welcome at their house anymore. He didn't mention any hard feelings about me, just didn't want to feel uncomfortable around his own house. He asked that she not try to initiate sex with him because he wouldn't feel right about it anymore. She is going to continue to live there until they can get their stuff separated and hopefully transition to a comfortable friendship. When we are together it will be at my house or out.
Overall, I think this is all the best that could be hoped for. I do hope she maintains a friendship with him. Though he told her that he doesn't think it will work since it never has for him. Probably they will end up being cordial, but not really talk much.
I didn't really feel like it was a poly relationship either. He and I never got along after about 3 conversations. It was much more her having two mono relationships. I've talked with her about what I would want in a poly relationship if we were to be in one again. Essentially I would want to feel like a family, not two people dating the same one. She agreed that is what she would want too, but she has told me (and him) that she had started to feel like it would be natural to be monogamous with me. She had never felt that with other people. So who knows.
I agree that we shouldn't move in together right away, and that it would be good for her to have some time alone if she wants it. I will try to not pressure her in that way. But when she does move out, most likely she will be moving to a city over an hour and a half away. There will be challenges in seeing each other very often. But I think we could handle it for a couple months if we make an effort to still see each other and "date" often.
Thank you for your encouragements.