Mary Crawley is one of the more polarizing characters in the hit period drama Downton Abbey. Some fans loved her for her icy demeanor and grace in the face of tragedy. Others despised her for her selfishness, snobbery, and bullying of her younger sister. The truth is somewhere in between -- the lady does have a heart -- but most fans fall in one camp or the other.

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As one of the main characters, Mary had plenty of moments to shine and many more to wreak havoc both upstairs and downstairs at Downton. Below are ten of her most annoying actions on the show, and believe us when we say the list could be much longer.

Sitting Out The War Effort

Not even Downton Abbey could escape the impact of the Great War. Many of the footmen shipped off to the front; Sybil gave up her privileged lifestyle to become an auxiliary nurse; Edith learned to drive, helped out on a tenant farm, and brought reading material to wounded soldiers.

Compared to her sisters, Mary didn't do much. She sang with Edith to keep up morale when Downton was converted into a convalescent home but otherwise spent most of the war years pining after Matthew. It seems she was not made for hard work.

Refusing To Bury The Hatchet

Sybil's death was a shocking twist that no one saw coming. Branson mourned his wife for seven years while raising their daughter Sybbie before he was able to move on. Robert and Cora were devastated over the loss of their youngest daughter. As for Mary and Edith, they began to realize the importance of their bond as sisters. Or at least, Edith did.

The feeling inspired her to make peace with Mary and ask if they might get along better in the future. Those hopes were soon dashed when Mary said she didn't think so.

Stealing Another Woman's Fiancé

Mary also took a long time to recover from Matthew's death in a tragic car accident. However, she had no trouble finding suitors in the intervening years. Among them was Tony Foyle, a childhood friend who was an excellent match for Mary on paper.

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Tony ended his engagement to the socialite Mabel Lane Fox to pursue Mary, who appeared to return his affections only to decide he wasn't such a great match after all. She could have made that clear from the beginning and saved Mabel the heartache.

Throwing Thomas Under The Bus

The world of Downton Abbey changed drastically over the show's run. By 1927, Carson had retired from service and Thomas had inherited his position as the butler. Everything seemed to be going fine, even if the world had changed and life at the great house was not what it once was.

Unfortunately for Thomas, Mary decided that he was in over his head for the royal visit and dismissed him from his duties. She brought back Carson from retirement instead, who it turns out also struggled to maintain control of the household.

Getting A Haircut While Edith Was In Mourning

Mary and Edith had a longstanding feud going back to childhood. You'd think they'd mature with age, but their fights seemed to get even more vicious as they got older.

Mary, for her part, showed little compassion for her sister, even after Edith received news that Michael Gregson had been killed in Germany. What could have been a bonding experience between two widowed sisters was ruined when Mary showed up in a trendy new haircut -- as if nothing terrible had happened.

Meddling In Carson And Hughes' Wedding

Mr. Carson had always been a father figure to Mary, so of course, Mary wanted to do right by him. Sometimes her efforts were more intrusive than helpful. For instance, she insisted that Mr. Carson and Mrs. Hughes hold their wedding reception in the Great Hall of Downton Abbey, which was very generous of her except that the last thing Mrs. Hughes wanted on her wedding day was to be a servant.

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It was also Mary who gave Mrs. Hughes permission to borrow one of Cora's coats for her wedding, resulting in a stern lecture from the Countess who was not aware of the invitation.

Ruining Edith's First Engagement

A driving force at the beginning of the show was the Pamuk scandal. Mary slept with a Turkish emissary who then died in her bed. Although Cora and Anna tried to keep the incident a secret, Edith eventually found out from the servants and wrote a letter to the Turkish embassy, revealing what happened.

In response, Mary just so happened to bump into Edith's beau at a garden party and hinted that her sister felt he was far too old for her. Edith had been expecting a proposal from Sir Anthony Strallan, but because of Mary's actions, she left the party sorely disappointed.

Ruining Edith's Second Engagement

Unbelievably, Sir Anthony was not the only one of Edith's beaus to be swayed by Mary's deceptions. After finding out that Edith would outrank the rest of the family as the Marchioness of Hexham, Mary dropped a major truth bomb on Edith's fiance: that the little girl Marigold was not Edith's ward, but her illegitimate daughter with another man.

Bertie immediately broke things off with Edith, and Mary looked a bit too smug and proud of herself in the aftermath.

Being Indecisive With Her Suitors

In contrast to her sister, Mary had no shortage of suitors after Matthew's demise. The search for a new husband was her main storyline until she began to assume greater responsibility for running Downton.

The love triangle in the intervening years felt interminable. There were times when we just wanted Mary to make up her mind already between Lord Gillingham and Charles Blake. Even more annoying, she ended up choosing neither of them when Henry Talbot entered the picture.

Valuing Wealth And Status Over Love

Mary's ability to blow up Edith's life was matched only by her habit of shooting herself in the foot when it came to romance. Mary did not immediately accept Matthew's first proposal because she followed Rosamund's advice to see if Cora would have a boy or a girl. If she had a boy, then Matthew would no longer be heir to Downton.

Mary's hesitation led Matthew to believe that she only wanted him for his inheritance. Over a decade later, Mary followed the same pattern with Henry Talbot, believing him to be a less than ideal match because he lacked a title. How annoying that with both men, she followed her head instead of her heart.

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