you go binary.
You're missing the point in focusing blame upon the victim of this murder. Of course, the murderer deserves primary blame but secondary blame rests with the system ostensibly designed to protect potential victims before they become victims. That system failed.
The system needs to be established so that vulnerable, sometimes unwise people can receive the necessary attention when they go to police and counselors. Talking about what the victim did wrong here in the grand scheme of systems is only useful for the system to identify potential problems to look out for.
But that wasn't his intent.