Creepy cousin

I have this cousin who is related to me both by blood and marriage, second cousin once removed by blood, first cousin by marriage (long story). I hadn’t seen him since we were six, until last year. I saw him at a party and he was WAY to friendly. He kept asking who I would kiss in the room if it was life or death. It was a FAMILY PARTY. Everyone in the room was related to me! I told him I’d kiss my cats forehead. But he said that wouldn’t count. I just ignored it, and afterward he kept texting weird shit like, “I’m crying rn, wyd” “Hey, I just banged my head against the wall until I bled” “wanna chat? Or not, I could just kill myself instead” “I’d rather date you than my gf” “You never told me who you’d kiss” “what would you do if I was in your bed with you rn?” “I saw my brother die in my dream last night. You were with us” “i love you. We’re family so it’s not weird. Now say it back. Say it back or it’s weird.” “*a picture of someone covered in self harm scars and open cuts* what would you do if I looked like this next time you saw me”

I stopped responding. I have a problem with suicidal thoughts and self harm. He doesn’t know that, but I can’t handle images like that or feeling like I’m responsible for his life. He was at another family party recently and I ignored him. He started texting me again and I just can’t. I haven’t responded, and whenever he’s active on the messaging app I use, I log off. I just set his account to “ignore” after he sent multiple “hey” “are you awake?” “Wyd” “it says you were active an hour ago” “where’d you go” “are you ignoring me” texts at one in the morning. Knowing that he knows where I live is.... I don’t want to think about it. I don’t think he’ll hurt me, I just don’t want to see him.