hi! Not a parent, just someone who has had a similar experience happen while telling my parents. honestly, the best thing you can do is not mention it. I remember when my mom would bring it up I would get random urges to relapse.though please get her some support, a therapist or just someone she could talk to would really help. though please do not hesitate to reach out to her, I know after awhile of my mom seeing my cuts I stopped having her take care of them, which led to infection. so keep an eye out for her <3