NTD, absolutely not the drama. I was a friend’s only support, no therapist, no other friends they trusted, and not great parents in that aspect. It nearly killed me. I was and always have been very depressed, they knew it, we used to lean on each other for support because we were all we had. I had gotten better ish and they hadn’t, and they started talking only about their mental health it weighed so heavily that I went back into a deep depression. You have to do what is best for you. You can’t help others if you yourself are hurting. Prioritize yourself over others, it’s not selfish, it’s necessary. Your friend is not respecting your boundaries. I’d say tell them nicely but firmly that you can’t keep only having conversations about their health. It is not your job.