I think people tend to blame victims because they prefer to deny their own vulnerability and the helplessness they would likely feel in the same circumstances. That, or they’re arrogant enough to believe they’d never find themselves in such a situation in the first place. Either way, it’s cowardly, selfish and unhelpful to genuine victims to blame them. I’m sorry you’re struggling today, but let us take our turn to help you!
It’s always good to take responsibility and precautions, but you can’t possibly predict everything bad that could happen and thus avoid it. It’s not your fault some people are abusers always looking for a victim.