NEW YORK, NY - APRIL 19: Lena Dunham, Allison Williams attends the 8th Annual Blossom Ball at Pier Sixty at Chelsea Piers on April 19, 2016 in New York City. (Photo by Nicholas Hunt/Getty Images)
Credit: Nicholas Hunt/Getty

As filming wraps on the final season of Girls, the cast has been faced with the heartbreaking task of saying goodbye to each other, the show, and the beloved characters they've worked so hard to bring to life over the past six years.

On Wednesday, Allison Williams closed the book on her character, Marnie Michaels, and took to Instagram to share the heavy mix of emotions she experienced leading up to her last day of filming the hit HBO series.

"How I'm feeling right about now," Williams captioned a photo of herself as a dejected Marnie from "The Panic in Central Park" episode from season five. "Today is my last day playing Marnie Michaels. Six years of passive aggression, folded arms and eye rolls...but also bravery, fierce protectiveness and ambition. I've loved you well, Marn. #WhatIAm #MarnieMarieMichaels"

Later that same night, Williams followed up that post with a pic of her and Lena Dunham wrapped in an emotional embrace.

"Marnie has officially gone wherever all characters go when we stop watching them. And I couldn't feel luckier that I got to play her. This lady, @lenadunham, gave me everything. She gave me the most incredible challenges and adventures and the opportunity to know and love our GIRLS family," Williams began the lengthy caption. "She also gave me her fierce friendship, wit, love, and loyalty, all while making me giggle on a constant basis."

Dunham—who created and starred in the show—is experiencing similar feelings about saying goodbye to her onscreen (and real-life) BFF. Dunham honored Williams on her last day with a photo of her friend arranging flowers in her hospital room after her endometriosis surgery.

"Instead of sharing a pic of Allison as the inimitable Marnie I'm sharing this: from a hospital stay I had where Allison came and organized my entire room, fluffed my pillow, put roses everywhere, installed an Apple TV AND made sure I had a buttered bagel," Dunham captioned the 'gram. "That's the most important thing to know about this woman. Yes she's gorgeous. Yes she's funny as f**k. But you will never have a better friend and sister. We are so lucky. I love you, Al. #MarnieForever #endofGIRLS"

After wrapping on three of the show's main characters—Shoshanna (played by Zosia Mamet), Jessa (Jemima Kirke) and Williams's Marnie—Dunham was left alone on set to close the story on Hannah.

"We wrapped Shoshanna. We wrapped Jessa. We wrapped Marnie. One more day. Only Hannah=Lonely Hannah. As Allison said, 'the cheese stands alone.' This is getting too real," Dunham wrote alongside a sad selfie that's got us feeling all the feels.

It's an end of an era for sure. Luckily, audiences can still enjoy the show for one more season, which will air on HBO next winter.