I need my fellow cosmos opinion

I feel like I'm a sell out. According to almost every form I fill out I am required to check a box that says I am white to some standard that categorizes me as such. It states that because I carry Spanish blood I am white. I don't agree with this at all. I'm sure most people know this, but humor me. You see, along time ago much of what is now Mexico was part of Spain, before it was part of Spain it was just land with natives. The Spanish invaded claiming the land and natives. Later that part of Spain declared its independence and became Mexico. Shortly after the USA and Mexico went to war resulting in Mexico losing land to the USA including the lands people. Now moving further to the present. I was born an American with full blown Mexican parents. I consider myself Mexican American, but must check white. My boyfriend is Native American and Mexican. His mother is full blown Native American and his father Mexican. His mothers tribe is an Arizona tribe. The USA acquired Arizona through Mexico. Today when we were both questioned and the case worker filled out the paperwork my ex-boyfriend clearly stated he was both Native American and Mexican to the case worker but he just checked the box for Native American. I then asked him if he was going to check white as well. He stated no because he's  Native American. I stared at him like oh okay. I don't hate white people or any race for that matter. If I was truly white I would be happy to check that box. But I am not white I am Mexican American damn it! Should I care? Hell yes I should care. Lol sometimes I check African American just because at least they give me a second glance and take time to ask about my race in depth. I hope that doesn't offend anyone. I want to know everyone's opinion on the subject. Please let me hear it, read it, whatever. Would you care?