A client told me vaccines cause autism

I've been diagnosed and I don't make any effort at hiding that I have autism. I'm a nail tech and I see all types of people. However, one of my clients decided to tell me that she thinks vaccines cause autism because of something she read. I didn't even know how to respond. It made me feel sick to my stomach. It's also solidified my desire to save up and become an independent nail tech. I've grown tired of trying to play nice when people say bigoted things to me because they haven't got the common sense to keep it to themselves.

I'm not really looking for advice for this, I just need to get it off my chest because it's bothering me a lot.