There are probably a few people you wish you could avoid--your mother-in-law, your nosy neighbor, or the woman at church who always asks you for a favor. Although you may not always enjoy their company, you know in your heart they mean well and that you shouldn't stay away from them entirely.

However, there are specific types of people who may actually be harmful to you both personally and professionally. These people are more than just annoying; they have traits that may be damaging to your self-esteem and to your emotional well-being. Here, six people you should avoid at all costs.

1. Bullies.

It's not just kids who get bullied on the playground, although that's often where it starts. A Canadian study found that, in the workplace, bullying is more harmful than sexual harassment. The study, which was presented at the International Conference on Work, Stress and Health, revealed that compared with employees who reported sexual harassment, bullied employees were more likely to quit their jobs, were more stressed, and had more anger and anxiety. The researchers speculated that the discrepancy may be due in part to there being more resources available to victims of sexual harassment.

2. Abusers.

Everyone deserves to live in a safe and respected environment, but abuse is more common than you might expect. According to a domestic violence symposium at Harvard University, half of all women will be in an abusive relationship at some point in their lives. If you or someone you know is in an abusive relationship, help is available. Often local resources can provide assistance; check with your local police station, YMCA, church, synagogue, or other place of worship. Or you can call the National Domestic Violence Hotline at 1-800-799-SAFE (1-800-799-7233).

3. Jealous people.

Often, people who display signs of jealousy do so because they're not confident in themselves. For example, a study published in the journal Evolution and Human Behavior discovered that short men were the most jealous, while very short or very tall women were more jealous than women of average height. The researches speculate that taller men and women of average height were least jealous because they are commonly considered the most attractive to the opposite sex and were most confident in their abilities to attract a mate.

4. Gossips.

Though it may seem harmless, gossiping at work can have serious consequences. People perceived as gossips may be passed over for promotions because they are seen as unprofessional and creating divisiveness among other employees, according to the University of Virginia Health System. In addition, gossip can increase the level of anxiety and decrease morale and trust in the office.

5. Toxic people.

These kinds of people take you away from other loved ones. They may demand all your time and become upset when you make plans for activities that include other people. In addition, toxic people will always look for negatives in a situation, finding ways to bring you down. It's best to limit your time or distance yourself completely from a toxic person.

6. Cheaters.

While it's true that an affair doesn't necessarily mean the end of a relationship—and, in some cases, shouldn't end a relationship—cheating is often a sign of a bigger problem. It's these problems that could signal when it's time to move on. There are 12 common reasons people cheat, according to the Zur Institute, which provides training for psychotherapists. Some of the reasons include these relationship-ending scenarios: avoiding conflict, getting back at a partner, and wanting to exit the marriage.