My boyfriend's parents... racist.

I had just had my son. he was about 3/4 months. I'm mexican amd he's as white as they come. We love each other and have been together going on 3 years. We have a son. My bfs mom and her brother and sister sat at the table with me and the baby while my bf was in the other room playing video games with his cousin. All of a sudden they start shooting questions at me. For example are my parents legal...? If my dad goes to Mexico how will he come back... I was in shock. I answered their questions and then told my bf I was ready to go. On the way home I started balling. The tears took over. I have never been treated like that before. The ordasity of the questions. I felt like complete shit. It wasn't my bf's fault. He felt so bad that he left me vulnerable to that.