Breakable Rule #1: Use "I" statements, not "you" statements, when talking about a complaint.
Sticking to emotion-focused "I" statements rather than accusatory "you" statements ("I feel upset" rather than "You make me so mad") has helped couples communicate more clearly and calmly for decades now. But there's a third option that may be even better, a 2009 study found: "we" statements, like "We need to find time" or "We should give it a shot." When longtime couples were discussing a sticking point in their relationship, those who used more "we" words (we, us, ours, and so on) acted more positively toward each other, showed fewer physical signs of stress, and were happier in their marriages overall. "You can use your language as an indicator of the current state of your relationship, like a gas gauge on your car," says Robert Levenson, a social psychologist at the University of California, Berkeley, who co-authored the study: Lots of "we" words and you're likely doing well enough to make it a long way; almost none and you may be running on fumes.
Breakable Rule #2: Never go to bed angry.
Half a dozen psychologists and therapists said they'd toss out this rule. Some problems simply can't be fixed in the 120 minutes between tucking in the kids and turning in yourselves. Sleeping on an argument can help both parties come at it refreshed later on—which isn't to say that you should lie in bed mentally gathering ammunition for your next attack. Psychotherapist Linda Young suggests concentrating on one of the best days you and your partner have spent together while you're falling asleep. If you're too angry for that, focus on any pleasant thought (as long as it's not about that old boyfriend from college).
Breakable Rule #3: Support your partner as much as humanly possible.
You want to be there for your partner when something goes wrong, whether it's a setback on a project at work or a disagreement with a friend. But offering too much support can be even more damaging to a relationship than giving too little, a 2009 study found. Married couples were less happy in their relationships when one spouse offered support beyond what the other wanted, like giving unsolicited advice ("You should talk to your boss") or frequently bringing up an issue they'd rather ignore ("Still pretty upset about what Jim said, huh?"). Unless your partner really doesn't want to talk about it, there's one kind of support that's by far the most likely to be welcome, says Erika Lawrence, a University of Iowa psychologist who co-authored the study. It's what psychologists call "esteem support": telling your partner you have faith that they'll figure out how to tackle the problem—full stop.
Breakable Rule #4: Be honest about your feelings, no matter what.
There's this idea that it's your feelings, so you can say whatever you want," says Alexandra Solomon, a clinical psychologist at the Family Institute at Northwestern University. People who hope to end up closer to their partners by sharing those innermost thoughts—no matter what they are—can find their relationships in trouble; it’s not called "brutal honesty" for nothing. You wouldn't tell your best friend, your mother, your coworker or even an acquaintance your feelings without taking theirs into consideration; don't do it to your partner, either.
Breakable Rule #5: Follow Ryan O'Neal's lead.
As he famously said more than four decades ago, "Love means never having to say you're sorry." But like sleeping without smudging your make-up or rushing to catch someone as they get on a plane, this advice only works in the movies. "Love means being willing to say you're sorry, a lot," Solomon says, "even if you don't really mean it, even if you didn't intend to hurt the other person's feelings, and even if you think the other person's feelings are kind of ridiculous."
Next: The relationship lessons we learn too late