My Lunch Friend Today Has Sores on Her Arms, Meth Use?

She is a new friend. We used to work together and I notice she always wore long sleeves and I though that maybe she was just cold, it was cold in there. But today on a hot 90 degree day she wore a black shirt with 3/4 sleeves and she had sores, old and new all over her arms, the arms that I could see. These sores were dimes size. Some were new and some were old. You could tell where some were scarred and healed. Some were kind of new. Sound like meth???
Teeth were ok but not great, she did sort of hide them a lot. I feel a bit torn as I get that she is trying to have a normal life and wants me to be her friend and be a part of it. She is kind. I can tell she knows that I’m totally clean and have never done anything like drugs ever before and I think she likes that. It’s not a trait I would ever choose in my friends, that the have done drugs before but I almost feel bad not being her friend. She is sooo obviously trying to lead a normal, productive life. She has an excellent job, 3 x my salary. Owns a big great home. Single but looking to marry. Gotta respect someone that has come from drug use to home ownership. But some of the sores weren’t exactly fresh but not exactly old either. I would say 1-2 months old, I work in nursing and I could tell by stealing quick glances that they had some time to heal. Not sure what to do.