One of the most important relationships in life is the one between you and your best friend. According to motivational speaker Jim Rohn, a person is the average of the five people she is around the most. You're likely to eventually adopt some of the characteristics of your bestie, so choose carefully. The result of a wise decision will be a supportive person you can trust and have fun with.

A Best Friend Is Loyal and Trustworthy

A friend is a person with whom you share a deep bond of loyalty and trust, notes the nonprofit website Help.org in the article "How to Make Friends." If a person is to qualify for the starring role as your best friend, he must be able to listen to your confidences without considering them fodder for the next day's lunchtime gossip. A best friend will put you first and not throw you under the bus for an acquaintance he's trying to impress. Only time will tell whether he has these qualities, so divulge personal information slowly until you're certain he's got your back.

A Best Friend Listens

While the friend who always has an entertaining anecdote to tell and who can hardly keep her mouth shut is entertaining, chances are she won't become a best friend. A bestie needs to have the ability to listen, as everyone needs someone to lend an ear now and then. When you have a problem, a good friend will listen carefully, offer you a shoulder to lean on and encourage you to come up with healthy solutions. When you show equal regard, the shared confidences can create a strongly bonded friendship.

A Best Friend Is Positive and Supportive

Having a positive, healthy friendship is good for your heart, immune system and overall well-being, says scientist and author David Hamilton in the article "Five Reasons Why Good Relationships Are Healthy" on SpiritLibrary.com. Positive interactions with your friend will bring you joy. Since you'll be spending a lot of time with your best buddy, it's important that he not drag you down. While he may have a bad day every now and then, he shouldn't have an overall negative personality if you want to feel uplifted when you're in his presence.

A Best Friend Is Genuine

The ability to keep it real is an important one for a best friend to have. While she may put on a front with other people, it's important that she be genuine with you at all times. "False friends can put deep scars on our hearts and big dents in our confidence," writes speaker and author Liane Holliday Willey in the "Psychology Today" article "Fake Friend Real Friend." Give carefully when you offer your friendship to someone, Willey advises. Most people won't have the capacity to be as genuine as a bestie should be, so it is best to relate to them on a more casual basis.