1. Never underestimate the value of asking your partner how his day went. Niceties don't become any less nice just because they become routine. At the end of the day, even if you felt like no one cared about anything you did, at least you know your partner will not only care but want to know details.

2. Some fights are just fights. They don't have to be deal breakers. You can be madly in love with a person and still be mad at that person. Fights don't have to spell The End. Couples that stay together choose the relationship over the conflict.

3. Accept that relationships come with obligations. You might not want to do everything your partner wants you to do with him — work events, seeing a band he likes, even errands — but you also know it makes him happy to have you by his side, which makes doing those things totally worth it.

4. But be honest about which events you feel strongly that your partner attend. Not everything can be a must. He knows to tell you that it's really important you attend Passover seder every year but will live if you decline an invite to his friend's Super Bowl party. You're both fair about it.

5. Little surprise purchases go a long way. Does your partner love mint chocolate chip ice cream? Picking some up while you're at the store shows you were thinking of him even while going about your boring everyday chores like restocking the milk.

6. Don't force group or double dates when all couples aren't friends. You don't have to share the same friends. It's OK to still go out one-on-one with your girlfriends, even if you all have significant others. The guys don't have to be friends just because you are, and not every conversation is a group conversation anyway.

7. Kiss hello before doing anything else when you get home. Kiss good-bye when you leave. It's always just the sweetest if he has to go to work extra-early but stops by to kiss you quickly while trying not to wake you. Or when he walks you to the door when you head out. And an immediate kiss when you reunite at the end of the day means you care about each other above all else.

8. Sometimes you have to say no to invitations so you can spend time with each other. Just because your calendar is blank one night doesn't mean you have to agree to plans if someone asks. Life gets weirdly busy as you get older. It's nice to use that free time to just be together.

9. Treat his family like yours. They love to know you think of them as family. And your partner will love to see you treat them like your own family. Call or text from time to time. Hang out with them when your significant other isn't around.

10. More "I love you"s are better than fewer. Three words that just never get old. You're seriously not going to say it too much.

11. Be sympathetic when your significant other is sick. Maybe it means canceling dinner plans and picking up soup. Maybe it means running to the drugstore for more cough drops. Don't complain. No one gets sick on purpose, and if the situation were reversed, you know he'd take care of you.

12. Take on more of the errands/household chores when the other one is swamped at work. No, you don't want to do laundry, but you do it to make your partner's life easier. And by checking things off your mutual to-do list, you'll be more likely to do things you actually enjoy together when his schedule frees up. Plus, you'll have a crazed period at some point too, and it all evens out in the end.

13. Don't make jokes at each other's expense. Be respectful and think about what he'd want you to share with a group. He's your partner, not your punch line.

14. Be on time. So many meaningless fights can be avoided by being on time. Start your eyeliner 20 minutes earlier than you think you need to. Chances are either you or your partner, or someone in the party you're meeting, is sensitive about punctuality, so be there when you say you will so you don't avoid anyone the wrong way and seem rude.

15. If someone talks shit about your S.O., defend him. Even if you're generally too polite to correct people or call them out on rudeness, sometimes you have to make an exception. After all, you're supposed to be each other's biggest supporters.

16. Keep each other informed of your individual plans. You're going to grab a drink with a friend after work? Great, have fun. But let him know where you're going to be so (1) he doesn't worry and (2) he knows you won't be around if he wants to make his own plans. It's not a matter of asking permission — it's a matter of being courteous because you always want to rest easy knowing your S.O. is alive and well and not in trouble.

17. Respond to each other's texts, calls, etc. No screening when it comes to your significant other. If he needs to get in touch for whatever reason, that should be a priority.

18. Choose not to fight when you travel. The luxury hotel you booked turned out to be not so luxury at all. Or he forgot to pack your toiletry kit like he said he would. You can get cranky and be That Couple having it out at the airport, or you can realize you'll have a good story or inside joke in the future.

19. Be spontaneous. Make a dinner reservation for just the two of you at the last minute. Or just wander into your favorite restaurant and eat at the bar. Have random morning sex. Surprise him with concert tickets. Keeping things unexpected makes being with the person you love even more fun.

20. Love each other unconditionally. Sometimes it really is just that simple.

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Headshot of Lori Fradkin
Lori Fradkin
executive editor

Lori Fradkin is the executive editor of Cosmopolitan.com. She worked previously at the Huffington Post, AOL, and New York Magazine. She lives in New York with her husband, sons, and dog.

Headshot of Amy Odell
Amy Odell
editor

Amy Odell is the former editor of Cosmopolitan.com. Chief amongst her interests are cats and Beyonce. She is a feminist (thank you for asking) and ex-fashion journalist. She is the author of the hilarious book of essays, Tales from the Back Row: An Outsider’s View From Inside the Fashion Industry.