Tw // self harm, cutt*ng

I've been very close with this person for a few months, and he's great! He checks in, asks how I'm doing, listens to what I have to say, and I feel loved by this person. But right now I am an emotional wreck. I partake in some methods of self harm, but I have never tried cutting. I understand it's an addiction and that he's in a rough spot, and he doesn't wish to give it up. But I can't personally understand the "why" of it, even if I can understand the pathology. It makes me feel guilty and selfish, but it really does trigger me and make me feel like I should compete with him, that I should accentuate my own self harm. I still want to be there for him, and I'd drop everything at the drop of a hat to support him, but it's tearing me apart because I feel like I can feel all of his pain. He cuts really deep and I am so deeply afraid for him. He cut so deep last night that he thought he would have to go to the emergency room. I only found out about it because he stopped telling me about it, but he posted about it on the self harm subreddit, and I feel a little sad that he wanted to keep that from me. He just told me that he's going to do the same thing tonight. I originally came here to ask what i could say or do to help him, but now I think I should really be asking if this is a healthy relationship or not. However, I also wouldn't want to stop being friends with him just because he self harms. It's just really getting to me. I am so distraught. I'm just so torn because he's always been extremely nice to me. I just need a hug.

Is there anything I can do? Anything I can say?