Love knows no bounds, particularly in Hollywood. Over the years, several high-profile couples have blurred the relationship boundaries as their romances began while they were still involved with other people.
And while they may be in love now, in some of these cases, the road to happily-ever-after was paved with some messy drama and broken hearts.
Scroll though the gallery below to check out a few of the celebrities who met their partners when they were still with someone else.
LEANN RIMES, EDDIE CIBRIAN & BRANDI GLANVILLE
Rimes "Can't Fight the Moonlight," but she can battle with her hubby's ex, Glanville! Ever since Rimes and Cibrian hooked up in 2009 — while the actor was still married to the Real Housewives of Beverly Hills star — the ladies have been throwing barbs, with Glanville once branding the country singer a "stalker."
But in April 2018, they finally called a truce. "The three of us sat and talked for hours [and] hashed everything out," Glanville tweeted. "The feud with LeAnn, Eddie, and I is over."
CLAIRE DANES, BILLY CRUDUP & MARY-LOUISE PARKER
In 2003, Danes fell in love with Crudup while they were shooting Stage Beauty — prompting him to leave Parker, his pregnant girlfriend of eight years! They split four years later, but Danes still defends the affair.
"I was just in love with him and needed to explore that," she told Howard Stern in 2015, admitting that she was young and careless at the time. "I was 24... I didn't quite know what those consequences would be."
ALICIA KEYS, SWIZZ BEATZ & MASHONDA
"You have no idea how much pain I was caused because of this affair," Mashonda said in a 2009 open letter to Keys. "You know the role you played and you know how you contributed to the ending of my marriage."
But the Grammy winner — who wed Beatz in 2010 — stands by the romance. "[They] were apart for some time before we ever got together," she's insisted. "There's no need to fight what's not true." Here's to hoping "Karma" doesn't rear its ugly head."
KENDALL JENNER, BEN SIMMONS & TINASHE
The model was fiercely private about her relationship with the NBA player — and with good reason. Simmons reportedly started dating Jenner while he was still with Tinashe. The rumors intensified when the singer's younger brother weighed in on Twitter and accused the pro athlete of cheating on his sister and breaking her heart. Simmons' romance with Jenner wasn't a slam dunk, either. After more than a year on and off, they split for good in early 2020.
NATALIE PORTMAN, BENJAMIN MILLEPIED & ISABELLA BOYLSTON
Portman swanned in and stole the show! In 2009, just one week before starting work on Black Swan, Millepied was snapping happy vacation pics with his live-in ballerina girlfriend, Boylston. But less than a year later, the choreographer and Portman were engaged and pregnant, with the Oscar-winning actress releasing a statement saying she was "indescribably happy and [felt] very grateful to have this experience." Boylston, probably not so much.
BRITNEY SPEARS, KEVIN FEDERLINE & SHAR JACKSON
"He cheated, he lied, he left," recalled the Moesha alum, who was pregnant with Federline's second child at the time. "There you go, in that order: cheated, lied, left." A "Womanizer," indeed!
BRAD PITT, JENNIFER ANISTON & ANGELINA JOLIE, LAURA DERN & BILLY-BOB THORNTON
Jolie made headlines when she broke up Pitt and Aniston's marriage in 2005. But as it turns out, it wasn't the first time she'd come between a co-star and their partner. Back in 1999, while filming Pushing Tin, Jolie met Thornton — who was engaged to Dern.
As the Big Little Lies star described in 2000, "I left our home to work on a movie, and while I was away, my boyfriend got married and I've never heard from him again." She added: "It was like a sudden death." Ouch!
BLAKE SHELTON, KAYNETTE WILLIAMS, MIRANDA LAMBERT, EVAN & STACI FELKER
When Lambert sings "We Should Be Friends," she's probably not talking to several scorned women! Evan, who the country singer dated before marrying Brendan McLoughlin, served his wife Staci divorce papers just 15 days after meeting Lambert in 2018. (They've since reconciled.) But this wasn't the Grammy winner's first rodeo: Her ex-husband, Shelton, was still with his first wife, Williams, when he fell for the "Vice" singer. It's safe to say Lambert has a type!
GISELE BUNDCHEN, TOM BRADY & BRIDGET MOYNAHAN
"I knew right away — the first time I saw him" is how Bündchen would describe her 2006 meeting with her future NFL player hubby. What she didn't know at the time was that he was the soon-to-be baby daddy of his girlfriend of the past three years, Moynahan!
The Blue Bloods actress and Brady split around the time he met Bündchen, but Moynahan has since said, "When you're suddenly pregnant and no one is standing by your side, even if you're in your 30s, it's a hard conversation."