Long-running sitcom The Big Bang Theory contains plenty of important friendships, but some are certainly stronger than others. While some of these friendships are likely to last a lifetime, some wouldn't last another week unless there were mutual friends involved.

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Bernadette and Leonard are not two characters you'd naturally put together. Although they may consider themselves to be friends, there are plenty of reasons why they might actually be less close than you imagine.

RARELY TOGETHER

Out of all the combinations that can be created from this group, it's fair to say that this is the least likely to be put together. If they aren't at work, they are probably hanging out with someone else, so Leonard and Bernadette are never alone together.

What's more, they clearly don't really want to be as they never go out of their way to try to make that happen. It's odd that there's never been an extended period of time where they have hung out, but what would they really do together?

FIGHT OVER PENNY

Penny and Bernadette are best friends while Penny and Leonard are married. There's a lot of contention, therefore, over who gets to spend time with her. Of course, both relationships are incredibly important to Penny so it's difficult for her to choose.

Leonard and Bernadette would likely see the other as an obstacle, holding the other back from their friend or partner. Sometimes they go double dating, but even when this happens it's almost as if they are fighting for attention.

THE SCAVENGER HUNT

During one episode, Leonard and Bernadette were put together as a team to take on a scavenger hunt. It's fair to say that their weak friendship was tested very quickly, as Bernadette picked with Leonard.

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When Leonard was driving, Bernadette quickly took the wheel of the car, complaining he was going too slowly. She talked him down from quitting the hunt after it caused an argument with Penny, and even suggested that he could be referred to as...another word for a cat.

BABYSITTING

Leonard never, ever babysits for Howard and Bernadette. Perhaps he is terrible with kids or maybe it's because so many others offer to help. However, it's so rare to see Leonard with the baby that we wonder if he's contributing much to the friendship.

There are other factors that could affect this, including the fact that Penny probably doesn't want the baby around either. However, the fact that Leonard never takes on the responsibility shows he's not that great of a friend.

ENJOYING RELATIONSHIP BREAKDOWN

Leonard and Penny drinking coffee at home on TBBT

There have been a few occasions that a breakdown of Leonard's relationship has made Bernadette actually feel better about her own. Rather than feeling sympathetic towards her friends when they are arguing, it almost gives her comfort about her own marriage.

It's not like Bernadette is campaigning for the two of them to get a divorce or anything, but when trouble is brewing, she enjoys sitting and watching with a bowl full of popcorn and a face that suggests she secretly happy with how this has turned out.

LACK OF SYMPATHY

Bernadette has a very distinct personality, and often shows a lack of sympathy of many people. Her inability to empathize also links to the fact that even people at work fear her a little bit. This translates into all her friendships, especially with Leonard.

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Leonard has been known to play the victim, and tends to look for emotional support from those around him. Bernadette is be one of the few who tells him to pull himself together, offering very little support.

TAKING HOWARD'S SIDE

Guys usually stick together, so if there's an argument between Howard and Bernadette ⁠— which there often is⁠ ⁠— Leonard is in a difficult situation. Even if he agrees with Bernie, he kind of has to side with Howard due to their friendship.

This can strain Bernadette and Leonard further, and makes it clear that Leonard is loyal to Howard first and not both of them equally. It does make sense, though, as he has known Howard for longer and spends far more time with him.

BAD INFLUENCE

The boys stand in line for a movie in The Big Bang Theory

In some ways, Leonard is a bit of a bad influence on Howard. While he certainly doesn't encourage how creepy Howard was towards women, Leonard does influence him in terms of his geekiness and some of the crazy plans they come up with.

Leonard has never exited that bubble of nerd culture, and thus, neither has Howard. Bernadette doesn't appreciate it very much but she has to accept it's part of her husband's life; she can sure blame Leonard for some of it, though!

DITCHING SHELDON

Leonard will look for every opportunity to ditch Sheldon as he has to put up with him more than anyone else. He will prey on unsuspecting victims and launch Sheldon at them, removing himself as quickly as possible.

He has pulled this move on Bernadette many times. There have been countless occasions where she has gotten stuck with the scientist due to Leonard's larger plan to rid himself of his annoying housemate. Bernadette has gotten Leonard back on a few occasions, however.

BELITTLING INTERESTS

Speaking of the geeky interests that both Howard and Leonard have, Bernadette is quick to belittle them. Whether it's the TV shows they love or the comic books they read, Bernadette treats them as if they are just big kids, never quite stepping into adult life.

Since Leonard's apartment is the place that they hang out in most of all, he is often the prime target of some of her jokes. His chosen field of study is also a little beneath her since she has chosen the financial path to success, so Bernadette belittles his profession, as well as his interests.

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