cutting when boyfriend disapproves

Shay
Hello all. I have been cutting and struggling with EDNOS for 8 years now. I am now almost 19 and my boyfriend and I are so happy together. When we first got together I stopped cutting completely. We promised not to hurt ourselves. Recently a family member of his committed suicide. It really tore me and him and our families apart. It feels like a blanket of depression has been thrown over everyone. I started cutting again. I'm terrified to tell him. I know I should stop but it's an addiction and I can't. I've tried. Obviously I'm not going to tell him until after all this with his family member committing suicide, but I don't even know how to bring it up. Last time I cut he grabbed my wrists and told me to stop or he would start doing drugs again. I don't know what to do. Thank you.