too much of anything is bad and in the case of drugs it could be lethal. but please be reminded that drugs are made to save lives, not to take them. and even how much drug you take, death is a matter of a divine power can decide and well explain.
just to put sense in your life, if it pains you loosing your partner, just imagine how it pains your partner seeing you take your own life from the other side.
there is hope my friend. if you are a christian, there is God, if not... there is magic.