Two things; find someone you can build a relationship on your own without his involvement and stop adding alcohol to this.
This seems like playful open sexuality rather than poly. Sport sex comes to mind. Maybe go swinging to help him achieve his goal of getting off with women he just wants to fuck with you? No biggy, just that it isn't poly and if you want a serious woman to woman relationship, it sounds like you need to do it alone. Besides, its pretty unlikely to work for the long haul with what you are looking for. Most triads of the nature you describe, that start the way you describe, crash and burn after the NRE sex ends.
The alcohol is bringing inhibitions down but for what? Sex. That can be not only dangerous and damaging, as you have had some experience with and is not poly. Again, open relationship maybe? Sport sex maybe? But as far as the descriptions that poly people usually use for themselves, not poly. I guess poly dating is kinda like this if you toss the word love in there maybe, but ya, not really convinced of that either myself.
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