Hi and Welcome to SR
It is not your fault that family drinks or drugs. Some addicted will put the blame on other people. It is just a way to justify their use. And some will truly believe that they use for a reason.
I know family and friends will help support you. And if you want to understand addictions from the people that have suffered with it. Ask here or the abuser form. I think that is why open meetings are good so people can get an understanding of both sides.