Friend of 10 years hard to be around?

So this friend of mine she and I have been friends for 10 years. Well she has kind of a dry personality but here lately it’s been awful. I’m not sure how to approach it bc the attitude she has had idk. Today we went and got our nails and toes done and even then an escape did not help her. My mom was just diagnosed with breast cancer and it’s possible stage 3. She was super rude before we went into the salon and was like “my aunt fought it 3 times it’s fine.” I get that but the way she said it like Gosh.. I’ve just been going through a lot and she’s just super attitude or dry about it hardly wants to talk. I’m not sure if I should just approach it or ignore it? Its hard we have been friends forever but its getting on my nerves to the point I don’t want to be around her. I try to do things with her bc I thought maybe she has lot going on at home but like I said the escape didn’t help either she just has major attitude the entire time. I don’t want to come at her hateful but damn sometimes I can feel I just wanna say something. Also every time I ask her if she is okay she just says “yeah why.”?