It’s a tough one. I’d say it’s good to fact check when someone has a story or series of stories, yes sometimes people can genuinely have been a victim but if this person is always a victim in the stories they tell and there’s no balance (like admitting their own part in circumstances) then red flags are there. Certainly where money changes hands it’s good to take your time making that decision and involve the second opinion of someone you do trust possibly.
Don’t beat yourself up though, we learn from experience, this was a tough one.