My best friend hates me and I might hate him too.

This is a little embarrassing to admit but he's an online friend, I met him two years ago through a mutual friend. If you asked me two months ago who my best friend is I would say him but now I just can't get myself to feel anything for him but hate. He had helped me through a lot but now all he talks about is stuff that leads to an argument. I genuinely can't remember when the last time was when we had a pleasant conversation. About five days ago he told me that talking to me makes him hate himself and me, after that he blocked me on tik tok. I begged him on discord to not leave me, I was completely deviated, crying and hyperventilating. He told me he would stay and not end the friendship but that him telling me he hates talking to me already ended it. We basically ignore each other now and I don't see this friendship lasting more than a month. I have to admit that I might have a mental illness of some kind but I try not letting it get in the way of my friendships, he knows what type of person I am and what triggers me. I can't remember him having anything nice to say, he always seems so negative and I hate him for that.