Dealing with a Toxic Friend

I used to be best friends with this one person. But then he started to think I was spending too much time with this other person and he thought that I was making them uncomfortable. So they started being very let’s just say “not nice”, and started to just ignore me. So yesterday I was texting them and I said hi and they just said “no”! Like wtf. Also I didn’t see them today so they texted me “are u dead” and I said “no” and I was about to at sorry about ever thing but they cut me off and said “aww too bad” apparently it’s was supposed to be a joke but that is not funny especially with all those similar thoughts I have, J don’t need another relapse.