pls help ㅜㅜ

i don’t know what to call this experience and i’m really confused. so i have this friend who is already dating my friend but wanted a picture of me to relive himself. he even went into detail on how he wanted to fuck me. i said no and how he made me uncomfortable but he just kept on insisting pictures of me. once i said no again he just went on how he’s going to kill himself and how horrible he is. he’s very suicidal and i took this seriously because he’s already attempted before. i felt so scared that if i didn’t sent one he would hurt himself. yeah it’s wrong that i sent him a picture when he has a gf but man i really didn’t want him to do something horrible. he does this again at another time but screenshots a photo of me. i said how uncomfortable i feel about it and i wanted him to delete it but he said to just not worry about it. he stopped doing this and seems to forget it but i don’t. he drops sudden hints on how he wants to fuck me or how cute i am but i just ignore them. he’s still dating my friend and she did found out his behavior but still kinda keeps going on. honestly i feel really uncomfortable and disgusting when he does this but i feel like he needs me when it comes to his mental health. i feel like if i just confront to him how horrible he made me feel he would say something how i made the choice to send him pictures to him and he isn’t wrong through. i just needed to vent ig i’m sorry