Depressed Ex-Boyfriend

We broke up in March. We were fighting a lot and sex was bad/unpleasant. We dated for over 8 years. He was very heartbroken. I didn't tell him the sex was bad obviously, but I told him I was tired of fighting and fighting. He said okay. And we stopped talking. A couple weeks ago, I deleted him from social media bc he was always showing how much he was drinking. He texted me and told me very depressing things, like how he's an alcoholic, drug addict now and it completely shocked me. He was never on drugs when we were together. He told me he was nobody and that he should just die. I asked him to go to church and try to find God. Anyway, he has texted me about how much he misses me. And last night at 2 am he texted me again saying he hopes God has mercy and let's him into heaven. I got really worried bc idk if he's thinking of hurting himself or what. I haven't replied and don't think I will. But I want to know your opinions. Am I doing the right thing by cutting him off completely? I'm seeing a really great guy right now, we're not officially dating yet but we're getting there. Obviously my ex has no idea and I hope he never finds out.