I have been faking a language barrier for four years and my husband has no idea.

My husband's family moved here years ago and they mostly speak Spanish at home. When we first started dating, I told him I only knew a few basic words from high school. He thinks I am just a typical American who can't learn a second language to save her life. The truth is I lived in Spain for three years and I am actually fluent. But I saw how his brother's wife gets treated. She is the official family translator. She has to go to every doctor appointment, every bank meeting, and deal with every annoying phone call for the entire extended family. Her phone never stops ringing and she looks miserable. I decided right then that I would never admit I understand them. If I did, my weekends would be GONE. Last night at dinner, his mother spent ten minutes talking about how my outfit looked cheap and how I probably don't know how to clean a house properly. She said it right to my face in Spanish while I was eating her cooking. It was ABSOLUTELY infuriating. I could of defended myself. I could of told her exactly what I thought of her attitude. Instead, I just smiled like a clueless idiot and asked for more salsa. My husband just patted my hand and told his mom I was "trying my best" to fit in. I feel like a liar, but then I think about my peaceful Saturdays without family drama and I realize I can never tell the truth. Why does being helpful always feel like a trap?