In any relationship, communication is key. Whether you've been seeing your partner for two weeks, two years, or two decades, communication is the cornerstone of any healthy and functioning relationship. Now add in the fact that you've been taught since birth that honesty is the best policy, and sometimes in the heat of the moment — these two policies can land you in hot water. Because believe it or not, there are things you should never tell your significant other. One of the best parts about being in a solid relationship is that you can say just about anything to one another. But even if you practice open and honest communication between you and your partner, some things are just better left unsaid.

For the most part, you're completely aware of when you're being blatantly mean or rude to your partner. But what about the moments that you're not aware of it? Sometimes, little things can slip out. Seemingly innocent things spring into your mind and out of your mouth, and they can actually actually be hurtful to your partner. Nobody's perfect. Sometimes your mind gets the best of you, and you don't realize you're doing the damage until it's already done. When one of the following phrases pops into your mind to say to your partner, take a step back and reframe the point you're trying to get across — because delivery is key, and there are some things that no partner should ever have to hear from another.

1. "Because I Said So."


Is there anything less sexy in a relationship than when you feel chided by your partner? You are not your partner's mother. Using phrases or explanations like "because I said so," can be detrimental to the health of your relationship. Making your partner feel like you're parenting them will make them feel like less of an adult, and make them more prone to acting out in the future.

2. "You're Just Like Your (Insert Family Member Here)."


As psychologist Gail Gross explained to the Huffington Post, this is just as bad as name-calling your partner. When you bring their family into the mix, you're insinuating that not only do you not like what your partner is doing, but that you don't like your partner's family, either. "An accusation is impossible to confront without being defensive," said Gross. When you accuse your partner of being too much like someone else, you take a bat to their self esteem. Even if they are acting just like one of their family members, it's important to remember that your partner is his or her own person.

3. "I'm Leaving."


"Never tell your partner you’re leaving, unless you really mean it," Gross said in the same article to the Huffington Post. When you threaten to leave your partner, you're triggering any abandonment issues they might have — not to mention it's the adult equivalent of crying wolf. Threatening to walk out on your partner only breeds distrust and rejection — two things no relationship should be built on.

4. "My Mother Said This Would Happen."


By introducing a third party into your conversation, whether it's your mother, sister, best friend, or anyone else, insinuates that you've been talking about this issue behind your partner's back. That immediately makes your partner feel as though they're in the red. Not to mention, it creates a distinction of there being a line in the sand. You and whoever you spoke to about it are on one side of the line, and your partner is on the other. By bringing up your confidant and their thoughts about your relationship, you're saying that you value their opinion more than you value your partner and his or her actions. Before you bring in your backup, try talking to your partner about whatever it is that's going on, and keep the conversation to just the two of you.

5. "You Always ________." or "You Never ________."


Psychotherapist Judy Ford told Woman's Day that using blanket statements only hinders a relationship. "These are two phrases I advise couples never to use," said Ford, "because they set up an instant, negative tone; they halt communication and they put the other person on the defensive." Rather than using always, or never, try and focus on specific instances for your partner. It's all in the way you approach your partner.

6. "He/She Is So Hot."


No matter how strong your relationship is, vocalizing a wandering eye is sure to breed resentment. Even if you do think this person or the next is beautiful, sexy, or mindblowingly hot — you don't need to tell your partner about it. Even if you're admiring a celebrity, chances are good that your partner will compare themselves to whoever you think is so hot, and take a hit to their self esteem. There's a fine line between being honest and being hurtful, and if you're unsure of how your partner will react to it, it's better to keep it to yourself.

7. "Can You Afford That?"


Finances are one of the most personal subjects in a person's life, but when you're in a committed relationship, they can become an issue. If you feel the need to sit down and discuss finances with your partner, instead of butting yourself into your partner's choices and criticizing them for it in the moment, pick a neutral time when neither of you are spending money to sit down and talk about it. When you question your partners choices, especially their choices that have to do with their freedom as an adult, you wind up sounding like his mother. "When you communicate a maternal 'I know what's best for you' attitude for long enough, he may even start treating you like his mother," Jan Hoistad, PhD, author of Romance Rehab, told Cosmopolitan.

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8. "Calm Down."


When you tell someone to calm down, you're only exacerbating the unrest in the situation. "It's as if you're telling him he doesn't have a right to be annoyed, which makes him feel like you're rejecting or ignoring his feelings," professional matchmaker Rachel Greenwald told Cosmopolitan. Instead of telling your partner to calm down or relax, acknowledge their feelings, and make sure your partner feels heard. By acknowledging how they feel, you'll reassure them that their feelings are important to you, and in turn, they'll feel more relaxed.

9. "Are You Really Wearing That?"


Judy Ford, psychotherapist and author of Every Day Love, told Woman's Day, that this kind of approach doesn't get anything concrete across to your partner. Not only are you insulting their ability to dress themselves, you're degrading them in an ambiguous way. Is it the shirt you don't like? Or the way it fits? Or the combination? Rather than doling out a passive aggressive insult, start with a compliment instead. Suggest your partner wears a particular piece of clothing you love, because it makes their eyes pop, or their legs look amazing. By softening your approach, you create an environment where you and your partner feel comfortable with one another, and trust one another. And when you've created that sort of environment, your relationship is better for it.

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