Sali con un argentino- soy estadounidense

I was recently dating an argentinian guy- we met online in September. I live in the US but he lives in Buenos Aires. I had a pre-scheduled trip to Argentina, and the first day we met, he kissed me, and was very sweet. The relationship rapidly escalated, he asked me to be his girlfriend, begged me to stay. The pace seemed unusual but I thought perhaps it was a cultural difference. There were some red flags, but I noticed them and decided to move past them, thinking that they also might only be weird to me because I am from a different country with different ideas of a relationship. For example, in the US people are known to be "colder" and Argentinians are thought to be more "passionate". However, after canceling my plane ticket home and staying for two months just to be with him, I got back home two weeks ago. He continued texting me, saying "I love you", etc. I found out Wednesday that he has a girlfriend, who he lives with, of three years. Of course, I asked him about this information, and he swore that it wasn't true. I wasn't convinced, so he told me "The fact that you don't believe me hurts me so much that we can't talk any more", which confirmed it for me.

However, I didn't want to believe that everything was a lie, so I had a zoom call with the girlfriend yesterday. I didn't tell her the reason for the call prior- she is an online tutor, so I booked a call through her website, hoping that he had been telling the truth and that through small talk "what did you do for valentines day?" she would be able to confirm that they weren't together.

Unfortunately, they are living together, and thinking about marriage and kids. I tried to tell her about my relationship with him, because she deserves to know the truth. On the zoom, she kept asking me not to say any more, that it hurt her too much. She seemed like she believed me, but wanted to stay with him and so didn't want to know more. All she knows is that we slept together- she asked me not to tell her more before I could tell her how long it went on, and that it continued until this Wednesday when I found out about her. She has my contact information so she can reach out if she ever decides to.

I feel deeply hurt. Betrayed, stupid, tricked, used. It left me with a really bad idea of men. I just don't know how to heal from this. Please be nice to me, I am already hurting a lot.

Edit: please don't think I am blaming Argentina for this man or for cheaters and liars. I LOVED my time in Argentina. You guys live in a beautiful country. All the Argentines I met were open and friendly. I hope to come back someday and I will always treasure what I learned about the country.