It's normal for relationships to be challenging. But when they exceed a certain level of stress, they negatively impact every aspect of your life: your business, your friendships, your health, even your mental stability.

One study shows that staying in a bad marriage can raise your stress level to the point where you're more likely to get heart disease (the number one killer of both men and women in the U.S.). Marriage and family therapist Sharon Rivkin says, "If you're in a bad marriage, don't underestimate the stress that you are carrying around."

If you're seeing the following signs of a toxic relationship, it may be time to seek help:

1. Passive aggressive behavior

If you can feel something is wrong but when you ask, "What's going on?" the other person says, "Nothing," but then punishes you by giving you the silent treatment ... that's passive aggression. One problem with it is that it doesn't leave much room for resolution of the conflict. If you don't know what's wrong, you can't fix it.

Passive aggressive behavior is often accompanied by gaslighting, or making the other person think they're crazy for even bringing it up. If you constantly feel like there's something off but when you try to talk to your partner about it you get shut down, you may be in a toxic relationship.

2. Volatility

A relationship with extremely high highs and extremely low lows that tend to repeat has a high likelihood of being toxic. This is especially true if you find it hard to predict when your partner will be upset.

Uncertainty has been demonstrated, over and over, to be very hard on not just human beings, but all animals. Study after study shows that not knowing what's going to happen, or how to avoid pain, spikes your levels of glucocorticoids (stress hormones).

A healthy relationship includes conflict, of course, but not all the time--and not to an acute degree.

3. "Jokes" that aren't really jokes

If your partner makes belittling comments about you but then claim they were "just joking," there's a problem. Emotional bullies not only drop subtle insults, but they often then try to make their victims look stupid or like they're overreacting.

The way you can tell: a good joke will make you feel included; a toxic joke will make you feel small, angry, and powerless.

4. Walking on eggshells

Ever hide your phone because you're afraid of what your significant other is going to say about a text from someone else? Are you afraid of going out with people after work because s/he might get jealous?

Healthy relationships are built on trust and open communication. If you often find yourself trying to predict what will make your partner angry and avoiding that (even if it doesn't always work), it could be a toxic situation. You don't do that kind of thing with your friends; why is OK with your significant other?

5. You feel like you have to ask permission

A mature adult relationship is comprised of two adults, and adults do not have to ask one another for permission. Yes, relationships require compromise and you should consider your partner when making big life decisions like whether to move across the country or switch jobs. But if you feel like you need permission to make plans with friends, or find yourself feeling uncomfortable about making simple choices without "seeing if it's OK" with your significant other, there's something wrong.

6. Constant exhaustion

Trying to predict someone else's behavior (or mood changes) is tiring. Do it over and over for months or years, and you will become exhausted.

In healthy relationships, both partners feel normal and relaxed most of the time. In toxic ones, the "good periods" that were so common at the beginning start to be fewer and further between, and rarely last long. If you constantly feel drained and exhausted in your relationship, it's time to think about exiting.

7. Becoming isolated

Part of the problem with the exhaustion is your motivation level for seeing anyone else, including friends and family. If your partner discourages you from seeing those close to you, that's a major red flag. But the more insidious issue is when you yourself stop making an effort to see the people you love out of sheer exhaustion. 

The first step when it comes to getting out of a toxic relationship is admitting there's a problem. Be careful, take care of yourself, and get help if you need it.

Arianna Huffington’s Simple Rule for Avoiding Toxic People
Published on: Feb 28, 2018