Even the most compatible, loved up couples will at least occasionally have an argument. And as long as the arguments are conducted with mutual respect and on a level playing field, not only are they normal, they're actually healthy.
But did you know there are 'good' and 'bad' ways to fight with your significant other? And there's also such a thing as arguing for too long?
We're not talking days or hours here, either. We're talking three minutes.
Why three minutes?
"Research says if an argument has gone for more than three minutes, it's too long, and you're not having a conducive argument anymore," relationship expert Melissa Ferrari told HuffPost Australia.
"The reason behind that is, when we're in an argument with our partner, we tend to 'scare' each other in ways such as using a loud voice, maybe jerky body movements or making certain facial expressions. Rolling of the eyes is one example.
"And so what happens is the amygdala -- which is a small, almond sized part of our brain -- goes offline. It goes into flight or fight response.
"After three minutes if you are going on and still doing those kind of behaviours, you're not likely to have an argument with a win/win outcome."
The win/win outcome
The win/win outcome is something Ferrari is passionate about and believes couples should keep it in mind while arguing. In other words, it's not about you being right and them being wrong, or you 'winning'. The aim of any argument with your partner should be about reaching a resolution.
"When we have a situation in an argument where it's win/lose or lose/lose, then you both lose," she said. "If your partner is unhappy, you're unhappy. If you are fighting to win, so that your partner will lose, then you both will lose.
"The aim of an argument should be to achieve a win/win result for both of you."
It's important to be aware that sometimes your partner might start to fight with you because it's a bid for affection. It may be that they are feeling ignored or hurt.
Of course, believing that now and actually acting on it in the moment are two very different things. What do you do if you're in an argument with your partner, it's gone longer than three minutes and things still aren't progressing?
"What's good to do -- and this is something Dr Stan Tatkin mentions in his book 'Wired for Love', is to look at something he calls 'leading with relief'. What that means is one person actually decides to help the other person feel a little bit better so the argument can progress," Ferrari said.
"So a phrase like 'sweetheart, I'm sorry I've upset you' or 'sorry I was wrong' can be helpful. Basically something that's going to evoke a more positive response. The idea is to diffuse the argument and head towards a win/win situation."
Face each other
Have you ever had an argument where you've paced around the apartment, not looking at each other? Or one person is furiously washing the dishes with their back turned?
"I think it's really important to face each other during an argument. People will argue in the car for example, and in that situation you can't see the nuances on the partner's face that might show they are feeling hurt," Ferrari said.
"If you are in front of your partner, you can tell if you've hurt them by their eyes, and that in turn will create more empathy in you."
Always argue in person
It sounds obvious, but no phone calls, no texts.
"Texts... you can't tell tone, you can't tell anything," Ferrari said. "And people get more confident to write horrible things.
"If you're not actually looking at your partner and are doing it by phone or text, this is how arguments escalate."
Don't say things you'll regret
When your emotions are running high, it can be easy to lash out and say something hurtful to your partner that you really didn't mean at the time. Ferrari's advice? Don't.
"Be aware of your partner's vulnerabilities. If you know that you are going to say something that really is their Achilles' heel, and is really going to hurt them, then you're not fighting clean," she said.
"But what many people don't realise is, if they're going to hurt, you're going to hurt. That's what we call a two person psychology. A couple is a system. If one isn't doing well, you both won't do well."
Take time to calm down
If the fight is a big one (so we're not talking about someone forgetting to take out the rubbish here), and you have a high emotional response, don't launch into the argument straight away.
"If you are really completely flooded with negative emotion, like really really angry, it's worthwhile to take 20 minutes so your body and nervous system [can] reset," Ferrari said. "And then you can come back to it.
"Because when we are arguing, we start to lose sight of what we are arguing about because our system has gone into that fight/flight response.
"That's when you end up saying 'How did we get onto this? This isn't even what we're fighting about'."
Think of why you might be fighting
If you feel like your partner has really been on your back lately, take a minute to think of why that might be happening.
"It's important to be aware that sometimes your partner might start to fight with you because it's a bid for affection," Ferrari said. "It may be that they are feeling ignored or hurt.
"Think about how the communication between the two of you has been recently. And probably my last point on that would be -- and I think this is really, really important to remember -- when stress goes up, communication goes down. So that could be a factor to consider."