How I Met Your Mother: 10 Worst Breakups

For a guy who literally wrote "The Bro Code", sleeping with your best friend's ex seems like a situation you would never let yourself be found in.

Yet that's exactly what happens when, in season three, Barney has a one night stand with Robin. While Robin reassures Barney that "it never happened", Barney finds himself unable to act normal around Ted, engaging Marshall's services in trying to alleviate his guilt through possible legal loopholes surrounding what he did.

Alas, there isn't one, and Barney decides he will tell Ted when he picks him up in a limo on Ted's birthday for a spontaneous trip to Atlantic City. Before the limo can get going though, Ted tells Barney that he knows what happened because Robin confessed everything.

While initially it seems everything is OK, the scene immediately shifts to one of anger, with Ted loudly dressing down Barney and delivering a blow below the belt.

However, the next punch Ted verbally delivers is even more painful, telling Barney that he doesn't have a use for him anymore. The exchange between the two when Barney asks "Are you saying you don't want to be bros anymore?" and Ted's reply of "I'm saying I don't want to be friends anymore" is tragic, and relatable to anyone who's ever had a falling out with a close friend.

These two would salvage the friendship in the season finale, but the episodes in between were filled with tension and uncertainty, just like any bad breakup.