Melanie Griffith and Antonio Banderas  called it quits this Summer after 18 years of marriage, and we have to say, we didn't see the longtime duo's separation coming. They weren't the first famous couple to shock us with their breakup — Katie Holmes  and Tom Cruise 's divorce came out of nowhere and we couldn't have been the only ones who thought Jessica Simpson  and Nick Lachey  would last forever, right? Scroll through to see all the celebrity duos that made us gasp when they didn't make it.
Melanie Griffith and Antonio Banderas
Despite both having been previously married, Melanie and Antonio managed to make their marriage last 18 years before it was revealed in June 2014 that Melanie was divorcing Antonio .
Jennifer Aniston and Brad Pitt
They were Hollywood's golden couple and despite whispers that Brad was getting close to his costar Angelina Jolie , we thought that nothing could rock their solid relationship of seven years. In 2005, after more than four years of marriage, Jen filed for divorce just days after she and Brad were photographed looking sweet on a Caribbean vacation.
Keri Russell and Shane Deary
Keri and Shane revealed their split in early December 2013. The couple, who were married for almost seven years, had been separated since the Summer and are parents to a son, River, and daughter, Willa. They kept their relationship out of the spotlight, making their split all the more surprising.
Katie Holmes and Tom Cruise
Talk about the shock of the year! Katie and Tom's divorce announcement  came out of left field in June 2012, when Tom's rep shared that "Kate has filed for divorce." The couple were married for more than five years and have daughter Suri together.
Charlize Theron and Stuart Townsend
Charlize and Stuart, who were considered one of the most solid duos in Hollywood, kept their nine year relationship under the radar — so much so that even their 2010 split was a secret.
Amy Poehler and Will Arnett
We thought this funny couple would last forever, but there was nothing to laugh about when they announced their split in September 2012. They were together for nine years and have two children.
Susan Sarandon and Tim Robbins
They had been together for 23 years when they announced their separation in 2009. Despite the fact that they never married, it came as a total shock since their seemingly solid relationship had spanned more than two decades.
Heidi Klum and Seal
It was a huge surprise when Heidi and Seal's separation made headlines in 2012; after all, they had been renewing their vows yearly since their 2005 wedding . It didn't help that they frequently showed red carpet PDA and often gushed about each other in interviews.
Reese Witherspoon and Ryan Phillippe
Reese and Ryan were young and in love, and when they broke up in 2006 after seven years of marriage and two children, many fans were devastated.
Gwyneth Paltrow and Chris Martin
Gwyneth and Chris were married for more than 10 years and had 2 children together when they announced that they were "consciously uncoupling." Though Gwyneth had some cryptic quotes on marriage  through the years, we thought they would make it work.
Jennifer Lopez and Marc Anthony
In July 2011, J Lo and Marc released a statement saying, "We have decided to end our marriage. This was a very difficult decision. We have come to an amicable conclusion on all matters." The news came as a shock to many, especially those who had watched them give a sexy performance together on American Idol just months earlier.
Courteney Cox and David Arquette
Courteney and David had been together since forever — 1999, that is – and even though things seemed a little shaky, there was still hope that they were rock solid. In 2010 the duo shared a statement about their separation, and in 2012 their divorce was finalized.
Jessica Simpson and Nick Lachey
How could you not feel like you knew Jessica and Nick personally after watching Newlyweds? The closeness made their 2005 split news all the more shocking, despite months of denials that their marriage was on the rocks.
Demi Moore and Ashton Kutcher
Even with cheating rumors surrounding their marriage, we had high hopes that Demi and Ashton would make it work, especially given all the gushing they did about each other. But that was clearly not the case when, in November 2011, Demi filed for divorce, saying, "As a woman, a mother and a wife, there are certain values and vows that I hold sacred, and it is in this spirit that I have chosen to move forward with my life."
Vanessa Paradis and Johnny Depp
They may have never made it official with a wedding , but we were sure Johnny and Vanessa would be together forever. Fourteen years after they first started dating, the duo called it quits in June 2012.
Idina Menzel and Taye Diggs
In December 2013, Taye Diggs  and Idina Menzel announced that they were separating after 10 years of marriage. The couple met while starring in the Broadway production of Rent in the mid-1990s and have a son, Walker.
Maria Shriver and Arnold Schwarzenegger
This high-profile couple had four children and 25 years of marriage under their belt when news of their split was released in 2011. If that wasn't shocking enough, news of Arnold's love child and affair with the family's housekeeper followed.
Jennie Garth and Peter Facinelli
This low-key couple revealed they were ending their 11-year marriage in 2012. Jennie later said  that Peter's decision to divorce was like "getting the rug pulled" from under her.
Ashley Judd and Dario Franchitti
Ashley announced her divorce from her race car driver husband in January 2013. The couple was married for 12 years, and given their out-of-the-spotlight status, we didn't see it coming.
Miranda Kerr and Orlando Bloom
This was a couple we thought would weather all storms! In October 2013 they shared that they had separated after three years of marriage. They couldn't have been more adorable with their son, Flynn, and it doesn't look like those sweet photos ops will have to end. When a reporter asked Orlando if he was still friends with his ex, he said, "We're not friends — we're family."