Starting a business is one of the most challenging things you can do. And one of the hardest parts is that most people won't understand why you're working so hard, especially when you're not making much money to start.

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They also won't understand why you're spending so much time away from them.

Some of these people may even resent you for starting a business. They'll try to drag you down emotionally, tell you your business idea is silly and impossible or even try to sabotage your efforts. You may think that explaining yourself to these people will make things better. But in most cases, explanations won't help.

The best strategy for dealing with negative people you come up against when starting a business is to avoid them completely.

Research supports this view: A study in the Journal Of Social & Personal Relationships found that ignoring negative people increased the ignorer’s intelligence and productivity. The researchers examined 120 participants who had been asked to either talk with or ignore people who, in turn, had been instructed to either be friendly or offensive to the participants.

After four minutes of interaction, each participant was given a thought exercise that required good concentration. The participants who had ignored the negative people performed better on the thought exercises than those who had engaged with the negative people.

The researchers therefore concluded that avoiding negative people during adverse social interactions conserves mental resources.

Avoiding negative people, then, seems critical to staying smart and productive while starting a business. If you want your startup to be successful, make sure you avoid the following seven toxic people:

1. The person who tells you you have only one choice.

You never have only one choice. When someone gives you an ultimatum and tries to make you choose between only two things -- them or your business -- take a step back.

Offering a single choice to someone who actually has many choices is known as Hobson’s choice. Thomas Hobson was a stable owner in Cambridge who told his customers they could choose to either take the horse in the stall nearest the door or take none at all. (Of course, those customers also had the option of going somewhere else to get a horse, take more than one horse, steal a horse and so on.)

The “or” was an illusion, however. Realize that “or” is a power play: You always have more than two options. The next time someone gives you an “or,” say "no thanks," you’ll take both. Turn “or” into “and.”

Or, flatly refuse this toxic person and turn your focus back to your business.

2. The person who tries to make you believe you need him or her to be successful.

You don’t need someone else to be successful. Networking and surrounding yourself with positive people is a force multiplier in any venture, but the notion that you need other people to be successful is unhealthy. It opens the door to people using you for their own private gain. Need then quickly turns into neediness, which quickly turns into full-blown dependency.

So, be wary of negative people who try to make you feel like you can’t do something on your own. If someone starts withholding support from you unless you do what's demanded, ditch that person. Cut the cord and find someone else who will support you and your business efforts without any ulterior motives or strings attached.

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3. The person who tries to make you feel that it’s your duty to take care of them.

You are not responsible for other people’s happiness. When grown men and grown women try to make you feel guilty for not spending time with them or not doing what they want, it’s simply a power play. They want to control you.

If you act as a crutch for people like this long enough, your mind will become conditioned to sacrificial thinking. You’ll start to believe that you have to sacrifice your happiness for others to be happy -- that you have to sacrifice your success for others to be successful. But this is Hobson’s choice all over again.

Remember, you can have both. You and other people can be happy and successful at the same time. The problem is that some people don’t want to be happy and some people are too lazy to be successful. You’re not responsible for these people. So, let them go. Stop being their crutch.

4. The person who keeps reminding you about your past mistakes and current shortcomings.

Is there anything more annoying than finally making a positive change in your life, only to have someone close to you remind you of how many times you've messed up in the past? Everyone makes mistakes. Everyone fails. A lot. You have to let this go. You have to forgive yourself for everything.

If you don’t forgive yourself, other people will use your guilt against you. They will control you with your past. They’ll make you believe that you’re not allowed to take risks because you’ve made too many mistakes in the past. Don't listen to these people. Instead, learn from the past and then let it go. The future of your business is much too interesting for you to stay buried in the past.

5. The person who slights your accomplishments.

When someone you know achieves something great, it’s normal to feel a slight twinge of jealousy. Your brain will immediately try to compare what the other person has accomplished to what you’ve accomplished. If the other person has accomplished something better or different than you, your brain will try to justify what happened so you don’t feel bad about yourself.

A mature person justifies other people’s accomplishments by getting excited for them and thinking, "Wow, if I work hard, I can do something like that, too." An immature person will justify other people’s accomplishments by saying, "They got lucky" or acting as though those others' accomplishments are worthless.

The only way to keep achieving bigger, better accomplishments in your new business is to cut out immature people who try to belittle what you achieve. At the same time, you have to be mature enough to praise other people’s accomplishments and to freely help them achieve more.

If you want to achieve great things in your business, start respecting other people's achievements.

6. The person who turns you into a worse version of yourself.

Everyone has someone in his or her life who brings out the worst in them. Maybe it’s a former, passive-aggressive colleague, a controlling relationship partner or a possessive family member. Whoever it is, stop letting this person hijack your personality. If you find yourself thinking and acting foolishly around someone, stop being around that person.

You know who you really are, and you know who you have to be to reach your business goals. So, always be the best version of yourself, especially when starting a business. And surround yourself with people who hold you accountable to being the best you.

7. Yourself (your own self-sabotaging thoughts and habits).

There’s only one person who can keep you from achieving your biggest goals -- you. You are either your own worst enemy or your own best friend. So, take a hard look at the bad habits and self-sabotaging tendencies that might keep you from achieving your business goals.

Often, people sabotage themselves because they’re afraid of succeeding. They’re afraid of losing their current identity. These people will make great progress toward a goal and then suddenly, right before achieving it, pull back.

The reason people pull back from success is because they are more comfortable with their past selves than their future selves. They’re uncertain of whom they will become (and if they can handle it), so they fail on purpose. You must avoid this part of yourself. Let go of the person you used to be and open yourself up to the person you can be. The success of your business depends on it.

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