I'm sorry that things ended so poorly. It really sucks when people aren't who you think they are. I think we've all been there in one way or another, but of course it's much worse when it's a partner.
Rationalizing is both very hard to resist and *very* important to resist. I am trying hard not to let my desires and hopes cloud my assessment of reality.
I appreciate that you've stayed open minded to the idea that poly can work for some people, despite the bad time you had. Best of luck to you and your husband!!