By the way, newtoday, I actually just skimmed some of your threads and saw you mention that in your situation, your boyfriend sometimes thought about being with you and just you alone at times. (from an old thread of yours).
Very early on in my relationship with "Derek," he said things along the same lines. He said, "I don't know what's going to happen. I may end up breaking away from her. We just have to see what happens."
I don't think I was with him for nearly long enough for that to become a serious option, but had I been with him a year or a year and a half, it may well have been that he branched off with me.
Mind you, that is not what I was looking for when I tried to reconnect with him. I wanted to be poly with him and her. But...I'm just pointing out that she apparently had some grounds for being nervous about me. I think it's always a threat when the person you love is seeing someone else. No matter what arrangement you have, your person can and will leave you if they just find themselves happy with another person.
Ahh, so crazy.