#haimy
It is not a contradiction one can only heal if they take personal responsibility, yet the fact that one comes from a broken home plays a huge role in there drug addiction, and when the child understands this it can really help them heal.
Also this concept of a broken home damaging a child is said in many places in Torah, here are some of them.
Rosh to Nedarim 66d
Brachos 7b
Milachim a6