Overdosing can be a suicide attempt. Sometimes however, the product is stronger than expected or takes longer than expected to have an effect and that causes accidental overdose.

In both cases mentally healthy people feel sorry for the person, because they were either in a tough spot and saw suicide as the only solution or they tried to feel good and had an accident instead. Some mentally healthy people supress their sadness though, which is a coping mechanism to not be overwhelmed by sorrow. They still feel it a bit, but focus on distractions etc.