Welcome to our forum.
It sounds like this guy is quite taken with this girl from Argentina, and probably caught up in NRE (New Relationship Energy), which could be clouding his judgment. For this reason, he may not be paying as much attention to your wants or needs.
You shouldn't feel like you regret communicating, because you have to communicate to get anywhere in a relationship, and usually more communication is better than less. For example, it's better to tell the other person exactly what you want or need them to do, rather than hope they'll care enough about you to figure it out. It's better to just come right out and say it.
It's not necessarily bad to tell him you're hurt, but try to do so without placing blame. It may even be wise to take a step back from the situation, and let him figure out what he wants while you figure out what you can live with. Obviously he wants this other girl in his life, so is that something you can live with? or is it a dealbreaker? That's something to mull over.
I don't blame you for feeling hurt, I would feel hurt too if someone attacked me like that. It sounds like a touchy situation.
I hope your time spent on Polyamory.com will be of help to you.
Love means never having to say, "Put down that meat cleaver!"