Is this a rude question

Do you think this was rude of my mom to ask ??

So my bf and I have been together for 5 years we have lived together for 3.5 years.

Today, my mom and I were talking about Netflix and Hulu. And I said that he pays for the Netflix and I pay for Hulu. And sometimes we get peacock, paramount , and max if there is a show or movie we want to watch.

So that prompted her to ask how we split all of our bills. And it made me uncomfortable that she asked me and it shocked me. I told her the truth and said what all he pays for and what I pay for. He pays a little more than I do, but he also makes more money.

But I found it to be an uncomfortable question, like it isn’t any of her business.

Do you think it was rude of her to ask that? Or do you think it’s normal and I’m overreacting?