Healthy relationships should involve equal commitment, honesty, and effort from both parties. There should be no underhandedness or manipulation in a good, well-functioning relationship. But many television romances are toxic and uneven. One partner gives so much of themselves while the other isn’t entirely invested and/or only takes advantage for their own benefit.

RELATED: 10 Worst Love Triangles In SitcomsAlternately, the “giving” partner is devoted to the point of obsession and codependency, making it a dysfunctional relationship. Viewers often look at such relationships and predict they will end in disaster. Unfortunately, much of the time, this outcome is precisely what happens unless the couple comes to a realization and changes their habits.

10 Nate Sees Cassie As A Replacement, And Cassie Becomes Her Worst Self

Euphoria

Nate and Cassie walk down hall together - Euphoria

In Euphoria, Nate and Cassie form an unhealthy relationship while Nate is broken up with Maddy. Nate justifies it by stating Maddy brings out the worst in him while Cassie does the opposite. But Cassie's desperate attempts to please Nate and catch his eye are uncomfortable to watch.

It becomes evident that Cassie doesn't bring out Nate's best aspects, and he becomes more controlling. Her new aesthetic, seemingly a combination of Maddy and Jules, speaks more of Nate remaking her into his ideal girlfriend instead of loving Cassie for herself. Meanwhile, Cassie becomes cruel and manipulative while she dates Nate, a sad outcome for a character who only wants the love she desperately craves.

9 Rachel Is Far More Eager About Joshua But Also Uses Him As A Proxy

Friends

Rachel and Joshua - Friends

Stung that Ross is marrying Emily, Rachel from Friends takes matters into her own hands. She impulsively proposes to her boyfriend, Joshua, who is stunned. Not only is he still hurting from a divorce, but he and Rachel also haven't been dating long.

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Their respective behavior defines their brief relationship. Rachel is cringingly overeager, while Joshua's recent divorce makes him hesitate. After Joshua rejects Rachel's proposal, he visits her to possibly reconcile. All it takes is one look at Rachel in a wedding dress, and Joshua flees, never appearing on the show again. Rachel isn't too torn up, showing that it was more about sticking it to Ross.

8 Marina Hopes That A Quick Marriage To Colin Will Hide Her Extramarital Pregnancy

Bridgerton

Colin Bridgerton and Marina Thompson from Bridgerton.

Marina from Bridgerton is a sympathetic example. She is pregnant out of wedlock in a society that doesn't support unwed mothers. If she hopes to save her public image or financial future, she needs to marry quickly before her pregnancy becomes obvious.

Interests clash when Marina attracts Colin Bridgerton. Penelope has long been in love with Colin, so she sees him being deceived by someone hiding the truth from him while pretending to be as enamored as he is. Both sides have legitimate points, but it is all for naught. Lady Whistledown breaks the news to the whole ton, putting the kibosh on Colin and Marina's elopement.

7 Angela Cheats Since She Cannot Commit To Either Andy Or Dwight

The Office

Split-image: Andy and Angela, Angela and Dwight - The Office

Angela from The Office agrees to marry Andy after a stilted courtship. It doesn't help that Angela only accepted Andy's date offer because she was angry at Dwight for killing her cat. Despite their engagement, Andy annoys her. She even obstructs the wedding planning with trivial requirements to complicate the process.

Angela also starts an affair with Dwight though she is supposed to marry Andy. When the two men discover this, they fight a duel for Angela, who is pleased with the prospect. In the end, however, it represents Angela's inability to choose. Dwight and Andy realize she played them both, and they simultaneously dump her.

6 Robert Idealized Lyanna While She Didn't Love Him At All

Game Of Thrones

Split-image: Robert Baratheon, Lyanna Stark - Game of Thrones

The tragedy of King Robert's character in Game of Thrones is that the loss of his betrothed, Lyanna, permanently affected him. He is too busy mourning her loss to engage in the realm's current problems or care about his disastrous marriage to Cersei Lannister.

RELATED: 10 Most Controversial Shows Of The Last Ten YearsHowever, details imply that Robert didn't really know Lyanna. In the original A Song of Ice and Fire, Ned notes that Robert never saw the "steel" underlying her beauty. Ned also corrects Robert's assertion that Lyanna wouldn't have protested his involvement in the tourney like Cersei. The one-sidedness becomes clear through Bran's flashback. Not only did Rhaegar not kidnap Lyanna, but she also loved him and married him in secret.

5 Tracy Is Used To Push Ted's Romance With Robin

How I Met Your Mother

ted and tracy hospital

The premise of How I Met Your Mother consists of future Ted telling his children the story described in the title. Despite failed relationships over the years, including with Robin, viewers expected Ted to find his happy ending with the titular character herself.

The mother, Tracy, finally arrives, and fans love her warmth, humor, chemistry with Ted, and character arc. The finale, however, kills off Tracy. Ted's kids point out Robin's emphasis in his story, which leads to their reunion. Viewers were unhappy and criticized how Tracy only exists to give Ted his children. Furthermore, the long-awaited character gets axed to prop up Ted and Robin, as if Tracy was a stand-in to keep him happy.

4 Andy Wants Ann To Wait On Him

Parks And Recreation

Split-image: Andy with casts in kiddie pool, Ann making face - Parks and Recreation

Andy and Ann from Parks and Recreation fell in love before the show's start and fell in love during college. But, similar to Roy and Pam from The Office, they show how people can outgrow each other romantically, even when they have been together for a while.

Ann is mature and driven in her pursuit of a nursing career, but Andy is lazy and unmotivated. The relationship concludes after Andy falls into a construction pit and breaks both legs. Ann takes care of him for weeks, but learns that Andy could have removed his casts sooner. He pretended to be helpless longer so Ann would continue waiting on him. Logically, the couple breaks up afterward.

3 Heidi Dumps Cartman After Finally Having Enough Of His Self-Absorption

South Park

Heidi with her back facing Cartman - South Park

Before her relationship with Eric Cartman ensues, Heidi from South Park is generally kind and amiable, although she too has her moments. But spending time with Cartman does a number on her. He gaslights her by claiming she is mentally abusive and that she makes him unhappy by not submitting to him.

RELATED: 15 TV Show Villains Who Are The Main CharacterThis, along with Cartman's threats to keep her with him and Heidi's inability to admit she made a mistake dating him, influence Heidi in the worst way. She adopts some of his negative mannerisms, like bullying and selfishness. But, when she realizes Cartman tried to have her killed, Heidi decides to better herself, and leaves him after rejecting another manipulation attempt.

2 Don Constantly Steps Out On Betty

Mad Men

Don Draper puts his arm around Betty in an episode of Mad Men

Don's relationship with his wife, Betty, in Mad Men is troubled, to say the least. He struggles with hiding his true identity from a troubled past while she is stifled and unfulfilled in her decorative housewife role. But Don's numerous affairs are unquestionably awful.

Though Betty is unhappy, she still tries to manage her domestic responsibilities, and stays faithful to Don. Don preserves the shallow image of the perfect life with his family and lucrative career, but sees other women. When Betty discovers his true identity as Dick Whitman, the road to divorce feels like a long time coming by that point.

1 Joker And Harley's Relationship Is True To The Comics

Batman: The Animated Series

Harley hugs the Joker

The Joker and Harley's relationship is notorious for being abusive on Joker's end, while Harley is madly devoted to him. The characters' dynamic in Batman: The Animated Series preserves these characteristics. Harley was originally a good and moral person. But after falling in love with Joker, he manipulated and brainwashed her into being his henchwoman.

The Joker, being his usual self, merely sees Harley as a useful tool that he can harm or implement on a whim. He treats her cruelly and tries to murder her more than once, but she keeps returning to him. Frighteningly, Harley has no real motivation to kill and be a villain outside the Joker's desires. Her obsession with him is just that strong.

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