Sorry you had to experience that drama, but I guess you needed to see for yourself after you really didn't want to accept that there were red flags all over the place. I hope you won't go back into the lion's mouth (back with this guy), because clearly he is fucked-up.
Yes, poly can work. I know personally know people who have been poly for 15 years. There are many members here who have good, satisfying, emotionally stable polyamorous relationships in a variety of configurations and number of people involved. Of course, any human relationship has its challenges. I always recommend people here read TruckerPete's blog
and Indigomontoya's blog
. They are married (to each other) and in a Vee.
Polyamory as a relationship structure challenges the status quo. It is different than what most of us in Western society have been brought up with. But just like monogamous conventional marriage, which according to some statistics has a failure rate (divorce) of 75%, polyamory works only as much as the people in it are willing and able to make it work.
The guy's a jackass and we all tried to tell you this. His girlfriend is a drama queen. I don't think any of us who are poly would see much success in this scenario because of the players
, not the playing field.