No matter how much TV tries to normalize it, there's never an excuse for cheating on your partner.
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Whether the couple ended things or not, the relationship became tainted the moment the trust was broken between them.
We created a slideshow below of 19 relationships that were ruined by infidelity.
Callie and Arizona - Grey's Anatomy
Callie had stood by Arizona's side through everything. Callie gave up so much to support her and attend to her needs after the plane crash. We feel for Arizona, but we don't sympathize with her decision to hurt her wife.
Finn and Quinn - Glee
Not only did Quinn cheat on Finn, but she convinced him that even though they had never had sex, he was the father of her child. Talk about lies and betrayal.
Ethan and Emma - The Lying Game
Ethan and Emma were already starting to lose their magic, but Ethan's kiss with Sutton sealed the deal. Was anyone else shipping Emma and Thayer at this point?
Barney and Nora - How I Met Your Mother
Barney and Nora weren't a main relationship in the series, but they did have great potential. It almost seemed as if Barney was a changed man when they were together, but he cheated on her with Robin and told Nora the truth while he was meeting her parents.
Piper and Larry - Orange is the New Black
When Piper went to jail she was still engaged to Larry, and the two planned on being together once she got out. But Piper cheated on Larry with her former flame, Alex, and Larry put an end to their relationship.
Josh and Liza - Younger
Team Josh all the way. The biggest problem in this relationship was Liza's lies and manipulations. Josh was able to look past everything she had done to him because he loved her so much. But it's got to hurt when you plan out an elaborate proposal only to see your girlfriend kissing someone else before you can get down on one knee.
Andy and Angela - The Office
To be fair, this relationship was horrible for a lot of reasons, but there was no excuse for Angela's behavior. She should have just ended her engagement to Andy, rather than cheat on him.
Wade and Zoe - Hart of Dixie
Zoe deserved a lot better than what Wade put her through, but fans didn't seem to care. For some reason, everyone was still completely on board with this relationship and treated Zoe at the villain for being hesitant to give him another chance.
Sam and Annalise - How To Get Away With Murder
In this case, both Sam and Annalise were cheating on each other. This was in no way a healthy relationship or one that fans were meant to root for.
Schmidt and Cece - New Girl
We do have to admit, that we still love Schmidt and Cece despite everything. But we can't condone what Schmidt did when he was stuck between Cece and Elizabeth. The couple would have been a lot purer without the unnecessary road bump.
Madeline and Ed - Big Little Lies
Ed is the best male character on Big Little Lies, and always has Madeline's back. He loves her deeply, which is what makes her cheating on him so painful and undeserved.
Blair and Nate - Gossip Girl
It's still crazy to us that Blair and Nate even tried to get back together after everything that happened between them. Not only did Nate cheat on Blair, but he cheated on her with her best friend.
Ross and Rachel - Friends
Sorry, but "we were on a break," doesn't cut it, Ross. Ross and Rachel's relationship was horrible for a lot of reasons, yet the way he tried to defend his horrendous actions was probably the most cringe-worthy thing about this "epic love."
Katherine and Eddie - A Million Little Things
Eddie messed things up big time. They may have a son together, but that doesn't mean Katherine should have to stay in a relationship with someone who betrayed her trust.
Dylan and Andrew - PLL: The Perfectionists
Dylan and Andrew were relationship goals ... or so we thought. They were lining up to be The Perfectionist's cutest couple until we found out that Dylan slept with Nolan. Dylan did do the right thing by telling Andrew the truth eventually, but that doesn't make what he did any less horrible.
Devon and Priya - The Resident
Devon and Priya's relationship fell apart relatively quickly. It was obvious that Devon was starting to have feelings for someone other than his fianceé, but his betrayal was still heartbreaking.
Kimmy and Fernando - Fuller House
Fuller House likes to forget that Fernando cheated on Kimmy, which is why they got a divorce in the first place. And it didn't happen just once, it was on multiple occasions. The family-oriented show used the situation for laughs and had Kimmy and Fernando get back together during the first season.
Beth and Dean - Good Girls
The series started with Dean cheating on Beth with his co-worker. She later found out that cheated on her with multiple different people, and cheated on him in return with Rio. This relationship can't be repaired, and we don't want it to be.
Bay and Emmett - Switched at Birth
It was hard not to root for Bay and Emmett. They were the best couple on the show, which is why we're still bitter about the route these two took. Was the cheating storyline really necessary?