I find people who are overly paranoid and mentally insert themselves into situations like a main character much worse than the people above though. They are easy to manipulate and ignite into self-sabotaging because they keep hunting for answers to made-up problems, nonexistent threats or jump to conclusions without evidence.

When they aren't able to agree to facts, they'll end up lowering their tolerance to what is believable. You can easily trick someone who is paranoid by feeding them sweet whispers of contrarianism and mutual aggravation against a certain threat of theirs and they'll trust you.