He has always told me that he loved me and would never lose me. That IF it ever came down to it, that he would choose to be monogamous with me rather than lose me, but when I finally said "I cannot do this anymore"...then he said the decision was mine.
Okay I'm sorry, rereading from GG's post. This reeks to me. I know the OP says she didn't go into this planning on being a cowgirl but that is what it looks like.
"Okay I'll try this poly thing but with the previso that if I don't like it you leave your wife for me."
I also don't see an honest effort to try as it's just been one long, "This makes me unhappy fix it!" thing.