The student who sold her the oxy is only guilty of illegal sale of drug- charge him with that. The judge did the right thing in dropping the wrongful death charge.
She bought it to get high, crushed it to get high, snorted it to get high - she alone is responsible for her death though I am sure it is not what she intended. Unfortunately, all persons using drugs know the risk of death with first time use or any time but it is a risk they are willing to take.
My sympathy to her family for their loss.