It's interesting how history repeats itself. In 2003 Friends hit its 10th season and fans became a little contentious when Rachael and Joey got together. Then, fast forward to 2009 and season 5 of How I Met Your Mother saw characters Robin and Barney enter a romantic relationship. The girl next door was dating the comedic ladies man all over again, fans weren't happy either time, history had repeated itself.

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Arguably, Robin and Barney actually worked better together than Ted and Robin ever did, but that doesn't mean they were the best TV couple ever. In fact, their relationship had a lot of problems, problems that should have resulted in a definitive breakup way earlier than the show's final episodes. Let's list them...

Robin - Barney Manipulated Her Into Marrying Him

"The Over-Correction" was a season 8 episode that saw Barney play out an incredibly elaborate play that would set Robin up perfectly for his proposal to her. Forgetting that as soon as he starts dating Robin's arch-nemesis, Patrice, and acting very out of character, Robin should have known what was up, he's actually being incredibly manipulative.

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Over the course of the episode, Barney uses all of his knowledge about Robin's likes and dislikes, what would hurt her and what would motivate her to get her in such a position that when he does pop the question she'll say nothing but "Yes". That level of planning and manipulation is next level sociopathy and Robin should have run a mile.

Robin - He Didn't Burn The Playbook

Entry 2 The Playbook

Back again to "The Over-Correction", during the course of the episode, Barney tries to really sell that he's committing completely and totally to Patrice by burning The Playbook. For the uninformed, The Playbook is likely one of Barney's most cherished possessions, used to chronicle all of his sexual conquests.

When Barney finally reveals his hidden agenda to Robin, he confirms that he had indeed burnt The Playbook, but not for Patrice, for Robin.  Except he hadn't. By season 8 episode 18 - only 8 episodes later - The Playbook makes a grand return. Robin lets it slide when it gets destroyed yet again, but let's be honest, she really shouldn't have.

Barney - Robin Tries To Run From Their Wedding

In the first episode of season 8, titled "Farhampton", Ted is called in to talk to a talk Robin out of her wedding day jitters. It turns out that these jitters are less "jitters" and more "the sudden urge to climb out of the window".

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Now, How I Met Your Mother often depicts overreactions in its characters, but this isn't one. Barney is also shown to be worried about the wedding in later episodes, but his manifest in changing his tie, not jumping out of a window and running for the hills. Barney never finds out about the attempted escape, but it's likely he'd start to rethink a few things if he did.

Robin - Barney Cheated On Nora

In the season 7 episode "Tick Tick Tick" Barney and Robin slept together, potentially rekindling their relationship. The only problem? They had cheated on their respective partners, Kevin and Nora. After a little soul searching the pair agree they want to be together and that they'll end their current relationships to do that.

This isn't the first time Barney's been unfaithful to someone, by the end of the shows run the guy's slept with over 200 women. Robin should have known then and there, regardless of her involvement that being with Barney was a bad idea. But then again...

Barney - Robin Chose Kevin Over Him

Not everyone came out of that sticky situation looking like a saint. While Barney may be un-trustworthy and a creep throughout the shows run, at least he stays true to his word. Following the heart to heart in "Tick Tick Tick" Barney follows through and splits up with Nora.

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Unfortunately, Robin doesn't stay true to what they agreed was best. When Barney runs to meet her at MacLaren's, in a scene that really makes you feel for him, he walks in on Robin and Kevin sat together, as a couple. Robin looks over to him and slowly shakes her head. He should have known then a there that she wasn't the woman for him.

Robin - Barney Once Sold A Woman

Barney does a lot of reprehensible things over the span of How I Met Your Mother's 9 seasons, but the one that might spring up the reddest flags, regardless of Neil Patrick Harris' charm, is when he admits to having sold a person. In season 3 episode "The Bracket" the gag goes over what women out there might be out for revenge against Barney.

He lists a few, but the most jaw-dropping has to be "At one point I am pretty sure I sold a woman. I didn't speak the language, but I shook a guys hand, he gave me the keys to a Mercedes and I left her there." Forget breaking up with him, maybe just avoid a relationship altogether?

Barney - Robin Was Blind To His Emotions

While Robin and Barney were initially separated, Robin moves into Ted's apartment for a while. Arguments over the little quirks of living with a roommate solve themselves in an inevitable way, the two become friends-with-benefits to release the tension.

The episode, aptly named "Benefits", sees Barney act increasingly stranger in reaction to the news. Turns out that the two having casual sex is driving him insane because he's still in love with Robin. Every single one of the core group figures out what's ailing Barney, except Robin. This lack of emotional blindness to someone she's also supposed to still have feelings for is probably grounds for Barney to move-on all together.

Robin -  Barney's A Creep

Out of the core cast of How I Met Your Mother, it's likely that none are more quotable - and by the end of the series - more lovable than Barney Stinson. But that doesn't mean he hasn't done, said, and implied the doing of some pretty creepy actions.

The first thing he says upon seeing Robin is "You just know she likes it dirty" not exactly the most romantic of first lines. Among that he's sold a woman (as previously mentioned), slept with an uncountable number of others (mostly through lying), and has acted more irresponsible than any other human being on earth.

Barney - Robin Still Had Feelings For Ted

Ted and Robin about to kiss in How I Met Your Mother

The final episode of How I Met Your Mother, titled "The Last Forever - Part Two", was somewhat of a contentious finale for fans. Due to the two actors that played Ted's future children having to commit the very human act of aging, their segments of the episode were filmed way back in 2005 with the rest of season 1.

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This meant that the conclusion of the show was set in stone years prior before it became obvious that they weren't right for one another. Regardless, the episode is still the conclusion, and it implies that Robin had always harbored feelings for Ted, especially considering their deal to just marry each other if they were both single at 40. Something Barney should really have questioned.

Mutual - They're Terrible For Each Other

There are a lot of breakups, get-togethers, and re-returns over the course of How I Met Your Mother's TV tenure, so you'd be forgiven if you'd forgotten that Barney and Robin had a pretty dramatic break-up prior to their eventual divorce. In fact, when they were together initially it was only the span of 7 episodes.

In the season 5 episode "The Rough Patch", Barney and Robin are shown to have driven each other into pretty bad respective conditions. Barney loses control of his weight, and Robin gets seriously agitated. This episode is proof that they should just mutually split something they do in the final scene.

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