My fiance is a Columbian immigrant

I met my fiance 4 years ago. He was here in America for work. I was 18, he was 22. He's stayed here on a work visa and when we get married he's getting a green card but I'm kinda worried he doesn't want go stay here anymore. He hasn't been home in 2 years and he misses his family. I was taking a shower and he hoped in because he needed a hug. When I asked what was wrong he Saud "I miss my family..." with tears pouring. I've met his family. They're amazing people and so welcoming and love to cook. They are also trying to learn better English so they can communicate with me better and future grandchildren/nieces/nephews/cousins. He seems more and more depressed about missing his family. Well... I have nothing here besides my friends. I have no relationship with my mother, my father is dead and the rest of my family is terrible. Maybe I should just become a Columbian citizen? I wanted some advice