Your best friends are some of the most important people in your life.

Close friends should be the people you can always count on to cheer you on when you succeed and comfort you when you fail. But what happens when your best friend also happens to be your biggest rival? Seasons and seasons of drama.

While we wouldn't want a friend like this in real-life we also couldn't get enough of watching these volatile BFFs break up and make up each episode!

1. Serena and Blair ("Gossip Girl")

Blair may have been sick of looking like "Darth Vader" next to Serena's "Malibu Barbie" but when B + S weren't trying to out climb each other on the high school social ladder they were always each other's shoulder to cry on.

2. Hanna and Mona ("Pretty Little Liars")

Mona may have hit Hanna with a car and cyber-stalked her friends for a few seasons...but she also fought hard to earn Hanna's trust back and risked her own life to find out the identity of Uber A.

3. Brooke and Peyton ("One Tree Hill")

While Brooke and Peyton spent far too long stuck in a love-triangle battling it out for the World's Angstiest High School Basketball Player: Lucas Scott, they were always best friend goals as long as they remembered to stick to the "hoes over bros" pact. Whether it was starting a fashion line, reuniting with an estranged relative or marrying the loves of their lives, these two Ravens always wanted to see the other one fly.

4. Effy and Katie ("Skins")

Both used to being the center of attention, Katie and Effy were destined for a rivalry from "Skins" very first episode. However, once they moved past the trauma of a drugged-out camping trip (and Effy trying to murder Katie with a rock) these two Alpha chicks started to realize that they had much more in common than either one wanted to admit.

5. Adrianna and Silver ("90210")

Sure, Silver had a bit of a boyfriend stealing problem, but Adrianna taking revenge by switching out her bipolar medication was just pure evil.

6. Buffy and Faith ("Buffy the Vampire Slayer")

The moment a second slayer showed up in Sunnydale we all knew some major drama was going down on the Hellmouth. Faith and Buffy made a dream team at first fighting vampires side-by-side, but once the Mayor brought with over to the dark side there was no going back.

7. Rory and Paris ("Gilmore Girls")

Although Paris originally saw Rory as her steepest academic competition, once she let her guard down she started to realize that Rory was one of the few people who actually understood her drive for success and that competitiveness eventually melted into respect. Over Gilmore Girls seven seasons, Rory and Paris went from high school rivals to college roommates and even stayed closely involved in each other's lives ten years later in the rival series!

8. Casey and Rebecca ("Greek")

When scheming senator's daughter Rebecca Logan slept with ZBT sweetheart Casey's boyfriend during the pilot of "Greek" an epic sorority war was ignited. From boy battles, rigged elections, and room-stealing Casey and Rebecca were constantly at each other's throats. However, they eventually were able to put their differences aside and team up to take down an even greater rival...

9. Rachel and Quinn ("Glee")

Quinn started out as the typical "mean girl," constantly mocking Rachel's appearance and lack of popularity. Even after they both joined Glee club, the two were constantly competing over the spotlight and Finn's attention. Considering intense their rivalry was at the start its incredible Rachel and Quinn ended up graduating from high school as one of the closest pairs on the entire show, even agreeing to regularly visit each other at college!

10. June and Chloe. ("Don't Trust the B- In Apartment 23")

Who would have thought that a show that started with one character "screwing another character's fiancé on top her birthday cake" would eventually evolve into one of the sweetest female friendships of all time in only one season?

11. Alison and Spencer ("Pretty Little Liars")

Of all the complicated friendships and rivalries on PLL, Alison and Spencer's relationship was always the fiercest. Spencer was way too ambitious to accept being one of Ali's loyal followers and Ali was far too stubborn to give up her power that easily. Honestly, its a shock one of these two didn't end up killing each other by the finale.