help, my gf is addicted.

We’re both 19, and we were doing 3000g tanks every week. I did them with her, but recently I started seeing how bad it was getting and I stopped, hoping she would too. Now, she’s been doing it every week for over a month now. I’ve tried talking with her multiple times about how I feel and how it’s really affecting our relationship. She lies to me about not doing it, trying to hide it because she knows I get upset. I’ve asked her to stop and get help, and she agrees but gets right back to the same thing the next week. It’s breaking my heart seeing her like that, and I know it’s just going to get worse. I love her and don’t want to break up with her, what should I do?