Since you touched on topics like loss of a family member, dealing with a brother who you believe is narcissistic and abused you, cutting, and relationship challenges with family, I'm tagging @parus @peach414144@georgette12@amberpep, who may be able to identify with some of what you've mentioned and provide support, @januaryjane.
Losing a member of the family or a close friend can bring on a large sense of loss. It takes time, much time to overcome this. Do cry, yell, scream or whatever it takes but when your id knows, then it will slowly, slowly become easier to accept. Take care, Peach. (we understand)