My 'friend' keeps using me for homework and coursework help.

Long story short my friend (can i even consider them one?) 'has ADHD' and thus struggles a lot with their school work and homework. Last year they almost got kicked out of sixth form due to being absent a lot and missing deadlines. They also sometimes have a hard time at home and I tend to sympathise with them. However, ever since year 13 has started and we were able to drop one subject (we had to do 4 AS levels) they're still the same and haven't been using the 5 extra hours we have for any school work.

Two weeks ago we got set 20-ish pages of reading for history coursework and were told to make some notes, and obviously, they didn't do it. I felt bad as they were complaining about being depressed and wanting to do something to themselves if they didn't get it complete. I let them see my 8+ pages of notes to skim over but they soon asked to borrow it which I agreed to because I felt guilty.

Since then we argued about them being manipulative and them using me for homework for all our subjects (e.g., copying my exam questions in Psychology) and she hasn't replied to my message yet about returning the notes which I need back for Thursday!!!

I don't know if I should go to our teacher and tell them about the situation but I'm scared of getting in trouble. I've tried to retain a clean record during sixth form (good grades, punctuality, organisation & homework) and if our teacher finds out I let her see my coursework and my notes I might get done for plagiarism, which isn't great because all my other subjects share the same exam board as History.

I feel so anxious and regret ever helping her, should I ignore the problem and re-do my notes or go to our teacher and risk getting in trouble?