I have a friend who needs to be liked by everyone and when one person does not give them attention she assumes that they dislike her. She won't even put any effort in getting to know the person that doesn't talk to her, she'll just assume that since they are not talking to her that they don't like her.
Then when something small happens she takes it as a personal attack. For example, said person bumping into her and saying "Oops I didn't even see you there". My friend will automatically become offended and assume that the person bumped into them on purpose and then she will respond something like "You better watch it next time" or something threatening! But if it was someone she was familiar with she would respond much kinder.
Now the person she was worried about truly dislikes her now because she came off as rude over a small inconvenience because she thought they were doing bad things to her on purpose. What is the explanation for this behavior?