The Big Bang Theory has spanned 12 seasons, and over that time we’ve seen many friendships develop and thrive. Some were expected and others we would never have predicted.

The dynamics between the growing cast have kept us entertained and amused over the last 12 years. While there are also some spectacular rivalries, Sheldon and Wil Wheaton being a highlight, it’s the friendships which really underpin the series.

So which friendships are the best? Whose relationships are true friendship goals and whose are nothing to aspire to? Here are the 5 best and 5 worst friendships in The Big Bang Theory.

Best: Leonard And Sheldon

Leonard and Sheldon in The Big Bang Theory

Leonard and Sheldon’s friendship is the linchpin of the series. The entire story centers around the pair of them and their interactions with others, especially their new neighbor, Penny.

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While they may drive each other crazy at times, the pair have a bond which shows how much they care for each other. Leonard is constantly helping Sheldon, giving lifts and accompanying him to appointments. Later in the show Sheldon accepts and embraces the huge disruption to his organized life after Leonard and Penny get together.

Worst: Howard And Sheldon

TBBT Friendships Sheldon and Howard

While deep down Sheldon and Howard do care for each other, watching their relationship can be incredibly uncomfortable. The banter between them crosses too far into nasty several times and then feels awkward and stilted.

The main issue is that they just don’t understand each other at all. It largely feels like they just simply tolerate the others presence. This friendship definitely wouldn’t last if the bonds between the others weren’t holding it together.

Best: Howard And Raj

The original bromance between Howard and Raj is one of the highlights of the series. While they have their ups and downs, they're always there for each other. Despite some occasional bouts of jealousy, they are still each others biggest cheerleaders.

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Howard and Raj have a friendship which has endured many challenges and changes and is a great example of a true bond. Shared interests and a desire to rib each other has led to a friendship which endures through whatever life throws at them.

Worst: Bernadette And Raj

Another friendship which always feels uncomfortable is that between Bernadette and Raj. Bernadette often comes across as resentful of the bond between Raj and Howard, and it spills over into her own relationship with him.

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Then there’s the way in which she plays on his love for her family, using it to manipulate him. The episode where she persuades him to do all her housework and odd jobs is a particularly cringe worthy moment. They just don’t gel and it’s so awkward.

Best: Penny And Sheldon

One of the most unpredictable but endearing friendships is that between Penny and Sheldon. It starts off very rockily but over time we see a real bond begin to form between the two. As the seasons pass by, they begin to understand each other more, forming a genuine friendship no one expected.

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An early highlight is when Sheldon is trying to buy Penny a gift. The amount of thought he puts in, albeit in his own way, is touching. What’s even more touching is her gift to him, Leonard Nimoy’s autograph and DNA.

Worst: Stuart And Everyone

Poor Stuart. He tries his best but he just doesn’t have a clue how to build good friendships. While his relationship in later series is great to see, his friendships never really get off the ground. The only real bond we see is between him and Howard’s mum, who adopts him as a surrogate son.

As the show continues we see him try and fail to fit himself into the group. There is a time when he bonds with Raj but it’s short lived. Mostly his attempt at friendships just feel awkward, uncomfortable and sometimes downright weird.

Best: Amy And Penny

It’s not an easy task being best friend to Amy, who can be incredibly intense, but Penny takes it in her stride. Over time the bond between them grows and we see some moments where they show huge affection for each other. One such time is when Penny hates the painting Amy bought her but is desperate not to upset her.

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This relationship is more fraught than most but we like to think that Penny genuinely cares about Amy by the end of the show. They aren’t an obvious match but they are a good one, bringing out the best in each other.

Worst: Kripke And Sheldon

While Kripke and Sheldon are usually mortal enemies, there’s a brief period when Sheldon attempts to befriend Kripke, for his own gain. He brings him into the fold, much to the dismay of everyone else. It quickly becomes clear that no one likes Kripke, who is abrasive and creepy.

Kripke doesn’t play nice with others and this fake friendship just comes off badly. Luckily it doesn’t last long and soon reverts back to type. The arch enemy dynamic plays out much better for all concerned.

Best: Bernadette And Penny

Penny and Bernadette in The Big Bang Theory

Bernadette and Penny’s relationship is one which evolves more than most. It starts off quite casually but deepens as both women become the breadwinners of their respective households. This helps to create more of a bond between the two, who have both come a long way from waiting tables.

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Bernadette and Penny have many similar personality traits and their fierceness can also make them fiercely loyal, both to each other and to Amy. Just don’t cross this pair, you will regret it.

Worst: Bert And Everyone

Bert welcomes Amy and Penny into his home on TBBT

Another stereotypical loner, Bert tries and fails to fit himself into friendship groups. He is seen as the weirdo, despite being nothing but kind to others. Seeing Bert rejected time and time again when trying to reach out to others is heartbreaking.

While some bonds do eventually form, most are short lived and never really develop properly, unfortunately for Bert. He tries his best but it seems like he’s never really good enough.

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