The only way that a broken and dysfunctional family can get back on track is to turn to God; each individual needs to repent, trust Jesus, and forgive each other. Read God's Word and pray. It may start with just one person but that can be the catalyst that starts the miraculous change in the family.
"For whatever is born of God overcomes the world; and this is the victory that has overcome the world - our faith."
1 John 5:4