There is a scene where two people smoke pot. She says that it's not like she is doing meth. The one character shares that he previously had a problem with smoking pot too much. The daughter also crushes up ambien that she stole from her mom and feeds it to her dad without him knowing beforehand.
Yes, it is discussed a few times but not shown. His boyfriend was found washed up on the shore. It seems like he jumped from a bridge and killed himself, but his dad acted as if it was an accident. The sister describes identifying his body as swollen from the water.