"Boundaries are a key component for couples who don’t get sick of each other," sex and relationship expert, Dr. Megan Stubbs tells Bustle. They're able to tell their partner when they need alone time, and they know what pushes their partner's buttons so they'll try to stay away from it. "If everyone knows the ground rules, it’s easier to play within the lines and minimize some of the pitfalls that come from not addressing boundaries," she says.

Research has found laughter can benefit your relationship in some really great ways. That's why Susan Trombetti, matchmaker and owner of Exclusive Matchmaking tells Bustle, "Couples that laugh easily and often, don't get sick of each other." Instead, they enjoy each other's company, and realize that keeping it light-hearted every so often can help them feel more connected.

Couples who don't get tired of each know that it's important to be supportive of each other. "They talk, communicate well, and depend on each other for support in life," Trombetti says. Being each other's support system can make facing problems much easier because they they can rely on their partner's to help them get through things. It is an important source of strength these couples derive from their partner.

When you've been together for a long time, the big vacations and grand gestures aren't as important as the small every day things. "They have learned to enjoy life’s simple pleasure whatever that means to them, whether it be going to Starbucks for a coffee on Saturday, listening to a song on the radio that they both love, or sharing inside jokes," Trombetti says. "It’s the little things that count and bond them."

"On average, couples stop going to bed together about three years or so into the relationship," Chris Brantner, Certified Sleep Science Coach at SleepZoo tells Bustle. According to Branter, 75 percent of couples don't go to bed together and research shows that couples whose sleep patterns are mismatched report more disagreement, less serious conversations, and less sex.

That's why Brenda Knowles, relationship coach and author tells Bustle, couples who go to bed at the same time are more likely to stick together for a long time. "There is something very comforting about falling asleep with someone by your side," she says. "If we go to sleep to an empty bed or wake up to one, we feel a pang of loneliness."

Although it can be difficult to make busy schedules line up, Knowles says a simple goodnight kiss before the other stays up to finish work or unwind is better than no bedtime ritual at all.

​Couples who enjoy each other continuously also tend to be highly responsive to each other. That means, if one person texts during the day, the other one does their best to respond quickly if they can. There are no hanging texts or huge waiting periods. "Gaps in communication leave us feeling empty and anxious," Knowles says. "When our loved one makes a verbal comment in hopes of attracting our attention, [we respond quickly]. This kind of close attention soothes us and makes us receptive to our partner."

"We subconsciously absorb non-verbal interactions," Knowles says. Positive ones, like maintaing eye contact while talking, holding hands while watching TV, or even giving each other a high five after completeting a project together, can make us feel comforted and seen. "The other night I was chopping tomatoes for a dinner salad and the cutting board kept moving as I chopped. My boyfriend put his hand on the board and steadied it for me so I could finish the task," she says. "It was a small gesture but I felt noticed and cared for."

Doing new things together is a great way to prevent boredom from settling in. Couples who don't get sick of each other know that. "Whether it’s learning a new sport (Pickle Ball anyone?) or taking a cooking class, learning something new as a team refreshes a relationship in a fun and educational way," Dr. Jill Murray, licensed psychotherapist and author, tells Bustle. "Plus, it gives them the opportunity to practice with each other."

Couples who don't get sick of each other make an effort to have sex and keep it exciting. "It's important to talk about your needs and desires, and listen to your partner's as well," couples therapist, Wendi L. Dumbroff, MA, LPC tells Bustle. "It doesn’t necessarily mean everything each of you might be interested in will happen, but being able to have honesty around your sexual desires is sure to create closeness and maybe a few fireworks here and there."

"Keeping some mystery in the relationship is a factor that prevents boredom," Dumbroff says. Couples who don't get sick of each other know how to ask the right open-ended questions in order to learn more about their partner.

According to Murray, instead of asking, "How was your day?" maybe try asking "What did you do today that made your proud?" It's a great "exploratory question" that will help uncover more of your partner's thoughts and feelings.

"I've found that when partners are responsible for themselves (i.e. they pursue personal growth, personal enjoyment, and social relationships), they're less dependent on each other to meet ALL of their needs," couples counselor, Mikela Hallmark, MS, LPC, tells Bustle.

Couples who don't get sick of each other, don't make each other their entire world. Instead, they have interests outside of the relationship. "They work together and function well in their relationships, and they're also content with who they are individually and how they're making progress in their own lives," Hallmark says. "When they come together, it's easier to find happiness in the relationship since they aren't disgruntled that their partner doesn't meet all of their needs."

Relationship aren't perfect because people aren't perfect. Couples who don't get sick of each other know this. "It's so easy to be dissatisfied with a relationship when you expect perfection," Hallmark says. But couples who don't bored of each other expect that their partners will have quirks. "Instead, they understand they've chosen a human person to partner with," Hallmark says. "That person has quirks, and so does the rest of the world."

"Life gets complicated and busy," Stef Safran, matchmaker and dating expert, tells Bustle. "However, if you don't remember to make time (sans kids, job responsibilities, and family) you could forget about how things were when there were less responsibilities." Couples who keep things interesting know how to prioritize the relationship and make an effort to be with each other. They don't just make time when they can, they fit time into their already busy schedules.

Pretty much any relationship can be one where two people don't get tired of each other. For the most part, it's not something that happens automatically. Couples who don't get sick of each other work at their relationship. If you and your partner make the commitment to put in the effort, there's no reason why your relationship can't be long-lasting and successful.