The point, I think, that both you and the person you're replying to forget is thus: Andy knowingly supplied drugs to a recovering addict.
Were Phil and Brynn going through issues? Yes. Would they have spiraled out of control to a murder-suicide without Andy's intervention? Unlikely, she had issues but cocaine makes you do crazy shit like imagine problems where they aren't. That can put you in an altered state of mind where you will take actions that your normal mind would refuse to do.
Andy's actions post-death, particularly towards Loevitz, are quite telling. Saying he placed a curse on Loevitz and more? Yeah, that's the actions of a sociopath. If he truly didn't introduce her to cocaine and cared about the family, he wouldn't be so flippant about the tragedy. The repeated assaults, sexual assaults, thefts, and strings of lies show what a sociopath he is, so this behavior is not outside the pale when compared to what happened around this situation.
Personal responsibility is a thing, and yes Brynn does bear the weight of the responsibility for her actions taken. However so does Andy Dick share in some measure by his own actions taken, and by his responses he seems to show zero remorse.
I hope he's convicted and thrown into genpop. His only saving grace is he's not a kiddy diddler. But he won't last long for his antics.