Sorry for your losses.
my wife and I found my son on our kitchen floor convulsing from a dilaudid overdose earlier this year. luckily he recovered this time.
im a recovering addict/alcoholic and I know nothing I say can remove the pain and guilt you feel.
thought my son had finally caught my addiction to AA, but I was obviously mistaken. try not to blame yourself for his death. he had a disease that doesnt care about age, gender, race, or how many lives it destroys.
the serenity prayer helps me most times, but not always.
prayers to you and yours.