Star-crossed lovers have been a present theme since Romeo and Juliet. Outside forces keeping two lovers apart as they struggle to find happiness is seen many times in movies and TV shows, but especially those TV shows aimed at a teenage audience.

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The drama and angst of keeping the couple apart often play well into the storylines of teen dramas, and whether it's a hunter falling in love with its prey or the universe actively conspiring against the couple in love, it seems to never get old in the eyes of TV writers.

Caroline & Tyler (The Vampire Diaries)

Caroline crying in Tyler's lap in The Vampire Diaries

Tyler and Caroline's story was doomed from the start. Her being a vampire and him activating the werewolf curse, it became dangerous for them to be together. A werewolf bite could kill - and almost did - Caroline, and Tyler never had the best control when it came to his newly-discovered abilities.

Though the couple made a valiant effort to be happy together, they were simply too different in the end, and Tyler being exiled from Mystic Falls ensured that their relationship was never the same, but they're still considered one of the best couples on The Vampire Diaries.

Freya & Killian (Witches Of East End)

Freya and Killian kissing at the party in Witches of East End.

Not only was she his brother's girl when The Witches Of East End started, but it's later revealed that she's cursed with dying young as well, being reborn over and over again. But despite the stars literally working against them, they find each other in every lifetime, drawn together because they're soulmates and then having to go through the loss of each other.

Of course, it is later revealed that Dash and Killian are also warlocks who are reborn over and over again, so even though they can never be together long, at least they can keep finding each other.

Clary & Jace (Shadowhunters)

Shadowhunters - Clary and Jace

A couple brought from a book to the screen, fans hoped maybe their journey towards happiness would be less star-crossed on Shadowhunters, but it turned out they were still plagued with the same little obstacle. Believing they're siblings definitely threw a wrench into this romance.

When they find out the truth and could possibly be together, Clary is de-runed at the end of the show and forgets all about the shadow world and Jace. However, the writers decided to leave this couple with an open ending, and in the final lines that these Shadowhunters characters have, Clary can be seen remembering Jace, despite her lost memories.

Marissa & Ryan (The O.C.)

Marissa and Ryan in the OC

Coming from drastically different backgrounds, this O.C. couple seemed doomed from the start. Ryan was pretty much homeless when they first met, and Marissa at first glance was a spoiled rich girl acting out. But they were both so much more, and the show did a great job at showing Ryan trying to make something of himself and Marissa's troubling reasons for acting the way she did.

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Their class differences aside, they never could quite catch a break, and it seemed, at times, that the universe was conspiring against them. When Marissa finally got her act together, she tragically passed away, leaving behind a gaping hole in Ryan's heart.

Simon & Alisha (Misfits U.K.)

Simon And Alisha In Misfits UK walking and sharing headphones.

The complexity of the love Simon and Alisha shared is unparalleled. Their storyline is heartbreaking and the audience can first see Alisha fall in love with future Simon, who comes back in time to save her life. Only she doesn't know that.

He sacrifices himself to save her and dies in her arms. Part of the complexity comes from Alisha loving the future Simon before she loves the past Simon, but the future Simon only exists because she fell in love with him. Simon willingly gets stuck in a time loop, just so he can keep falling in love with her forever. So they can never really be together, but they have those precious moments at least.

Cole & Phoebe (Charmed)

Phoebe laying her head on Cole's shoulder in Charmed

The trope of the hunter falling in love with what it hunts is legendary, and just the case in Charmed for Phoebe and Cole. She's a good witch, fighting the forces of evil, and he is a demon, so by definition evil.

Their story has a lot of ups and downs, and Cole even tries to cross over to the good side for a while, trying to regain Phoebe's trust, but ultimately they don't work out because his evil side wins. They can never be together, and Phoebe is forced to vanquish him in an alternate reality that Paige gets pulled into. But their storyline was a fan favorite and featured in one of the best Charmed episodes.

Scott & Allison (Teen Wolf)

An image of Allison and Scott standing on a bridge together in Teen Wolf

Though Scott and Allison start off as a regular couple of teenagers, they're anything but. Little do they know that Scott is in the middle of transition into a werewolf, and she comes from a long line of werewolf hunters. So they were doomed from the start, but they didn't let that stop them.

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Even though Allison eventually breaks up with Scott because she can't deal with dating a werewolf (even though she later has a thing with Isaac), it seems who they are and where they come from is a reason enough to stay apart from each other.

Buffy & Angel (Buffy The Vampire Slayer)

Angel and Buffy sitting in a cemetery on Buffy The Vampire Slayer

Not only was Buffy a Slayer and Angel a vampire, but it's later revealed that he loses his soul if he's ever truly happy, turning him into a murderous monster.

It is because of that fact they can never again be together fully, even if they do try a very tentative relationship after Angel gets his soul back. In a spin-off episode of Angel, he even becomes human and they are briefly together, shown to be extremely happy and in love, but he gives that up in order to save the world from a demon. It's a heartbreaking obstacle they can never overcome.

Ace & Nancy (Nancy Drew)

Nancy and Ace looking contemplative in Nancy Drew.

Not many people saw Ace and Nancy happening at the beginning of Nancy Drew, but as their friendship grew, so did their feelings for each other. The audience slowly saw them come to terms with it and saw Ace reveal his feelings towards the end of the season.

But just when fans thought they were going to get a happy ending this season, the big bad of the season revealed her true cards. She cursed Nancy, so if she ever acts on her feelings towards Ace, he would die. In an already angsty situation, the fans then saw Nancy push Ace away in a desperate attempt to protect him. Hopefully, the show is renewed and they can fight fate for a chance to be together because Ace and Nancy are a perfect couple.

Damon & Elena (The Vampire Diaries)

Damon and Elena kissing in the rain in S06E07 of TVD.

The universe had no idea what it was doing when it wrote that the doppelgangers were fated to be together. Because while it was true that Elena did fall in love with Stefan on The Vampire Diaries, it was her love for Damon that made her feel alive.

The couple was already in a delicate place when they learned of the prophecy delivered by the "vindictive pre-historic witch," Quetsiyah. But their faith in each other and in the love they shared was stronger than the universe, and they are the proof that even star-crossed lovers can make it work.

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