I'm very sorry to hear about your loss. Heroin is an awful addiction that has played an awful role in way too much of my life. Dax's music is great and has helped me through a lot, but I actually feel that way towards the indie band the Mountain Goats more. As much as I usually prefer metal and hard rock and that type of thing, it's just often really relatable songs about depressing subjects (drugs, abuse, suicide, depression) in a really upbeat style that sort of helps me keep the "you'll make it through" mindset. It certainly helps that the guy lived through a lot of that too (he ran away from his abusive father, took up heroin for a few years, took up music as a coping method after getting clean and working in a psych ward, a close friend committing suicide...)