Friends are as important to your well-being — if not more so — than family. Studies show the strength of your closest relationships lays the groundwork for how you weather everything else in your life, especially stress.

But would the people you consider your closest acquaintances call you a good friend?

Here are six qualities that Irene S. Levine, Ph.D., professor of psychiatry at the NYU School of Medicine and producer of The Friendship Blog, tells Cosmopolitan.com make for the best of friendships — plus a few tips on how to be a better pal if you come up short.

1. You're not constantly judging her. You may think issuing your humble opinion on another friend's life choices, wardrobe, appearance, or dating prospects is helping her out. But in most cases, unsolicited opinions just make you seem judgmental, mean, and potentially threatening. If you're looking to keep more friends around (and help them feel comfortable being themselves around you) try reserving your judgments and accepting them where they're at.

2. You're dependable. You don't have a history of flaking at the last minute, always. No shame in needing to reschedule every so often. But a good friend shows up for commitments — or at least knows how to warn well in advance when she might not be able to make something.

3. You respect the fact that your friend has a life outside of you. Accepting that your friend isn't always going to be free when you want her to be (nor prioritize your needs above hers every day) is essential, says Levine. Not granting someone enough space nor respecting her needs for alone time — or hangouts with other acquaintances (significant others included) — can make you come off as suffocating.

4. You make plans. Taking initiative to lock down time to hang is key in keeping a friendship going. Don't expect your gal pals to always be the ones reaching out.

5. You show your cards too. A willingness to share personal information (from the hangups you've had since childhood to your hopes and dreams for the future) is essential to making and keeping fabulous friendships, Levine says.

6. You're willing to compromise. A relationship is a two-way street, not a dictatorship. Sure, you thought spending the weekend in the country with a bunch of booze and no tech was ideal. But your friend may not have the funds to go in on a share-house. Plus, she may want to do something closer to home. Being willing to find a mutually satisfying middle ground is a hallmark of a BFF.

What if you're not a good friend? Rest assured, change is possible, interpersonal skills expert Jenny Taitz, Psy.D., ABPP, tells Cosmopolitan.com. Here are a four ways to start improving your friendships immediately.

Ways to Be a Better Friend

1. Practice your listening skills. Really hear what a friend you're chatting with has to say and convey you've gotten their messages by paraphrasing back to them what you're hearing.

Example: "Sounds like you're really worried that this new guy is going to bail on you like the previous one."

Ask your friend questions and (remember) don't judge. "Literally reflecting back what someone is saying and asking more really works," says Taitz. Example: "You're new job sounds like a dream! What do you love most about it?" Open-ended questions, says Taitz, encourage more meaningful conversations that make the both of you feel better.

Be mindful of whether you've been hogging the proverbial mic for the majority of your mutual time together. (Enough about me and my stressors. How are YOU doing? I'm dying to hear about your recent vacation!)

2. Reach out. And keep reaching out. If you have friends you seem to have lost contact with, Taits recommends spending a few minutes at the start of each week setting up plans with people you want to keep around.

Don't wallow in any frustration that you're always the one reaching out. It simply isn't helpful, says Taitz. Instead, do what works. Which is: See who's around on Saturday to offset any weekend loneliness, and move onto the next person if you don't get a response.

3. Be thoughtful. There's the "Happy Birthday" Facebook post you write to a pal and then there's the actual sending a card or arranging time to buy them a birthday drink. (You decide which is more likely to reinforce friend-to-friend bonds.)

Getting and staying closer to people requires putting in a little extra effort, says Taitz. Take the relationship offline and actually be present.

4. Put yourself out there and make new connections. If you feel you don't have enough people in your life, pursue activities you like and try to introduce yourself to others, Taitz recommends.

"Ask questions. Smile. Read social cues — like, does the person standing next to you in line for water at the gym seem rushed or open to a friendly chat? If they're open, try an ice breaker."

This may not lead to instant deep conversation, Taitz admits. But you might exchange names, get a bit closer the next time you talk, and set the stage for a newfound friendship you can apply all the above skills to.

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