It doesn't have to be Halloween for you to scare your boyfriend away. Adopt a few unpleasant behaviors, and he'll run away as if being chased by a dozen hungry zombies. If you know what to avoid, however, he won't get scared unless the two of you decide to check out the latest horror flick at the cinema.

You're a Negative Nelly

Here's a sure way to scare off your guy -- launch into the latest thing that's gone wrong in your life within five minutes of seeing him. After spending an hour going on and on about how your teacher hates you or your friend is backstabbing you, ask him how his day was. Chances are, he'll be so emotionally exhausted from listening to you that he won't remember how to string two words together. To frighten him even more, make critical remarks to him and roll your eyes when he says something that you think is dumb. To curb this behavior, make a zero negativity rule for yourself, advises therapist Harville Hendrix in the "The Huffington Post" article "Zero Negativity." Being conscious of the tendency will help you to nip it in the bud.

You're Too Needy

Men tire of relationships with needy women, says clinical psychologist and author Jack Ito on his personal website. Dealing with your anxiety over his female friends on social media or being forced to spend every waking moment by your side will quickly grow old. If you catch yourself feeling insecure, check yourself before you open your mouth and make an insecure-sounding comment about whether he thinks you're pretty. Allow him the opportunity to be a true partner and not simply a comfort blanket.

You're Obsessed

If you're convinced your boyfriend is the most perfect guy on the planet, you might not want to let him know it. At least not if that means calling him several times a day, buying him inappropriately expensive gifts or scribbling his last name after your first name in front of him. If you try too hard, he may pull back.To keep your guy from getting frightened, be affectionate, but curb your impulse to tell him that you want to apply to the same out-of-state college that he's going to.

You're Up and Down

While everyone has their ups and downs, taking this to the extreme will strike terror into his heart. If you're a sweetheart one day, and a miniature T-Rex the next, he won't know what to expect. When people don't know what to expect, they get anxious. When people get anxious, they usually seek to avoid the source of the anxiety. In this case, that would be you. Strive to keep your emotions on an even keel so he doesn't feel as though he's dating the female version of Jekyll and Hyde. If doing so is difficult, try engaging in mindfulness meditation. This practice can help to regulate your emotions, according to a 2012 study published in the journal "Frontiers in Human Neuroscience."