Content Warning: This article contains discussions/references to physical and sexual abuse, violence, kidnapping and homophobia.

Fans of Shameless know that every character has a complex personality. The characters on the show are lovable and have moments where they show their best side. However, there are also moments where the characters do something horrible and sometimes irredeemable.

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Despite moments of horrible behavior from the Gallagher family, the supporting characters on the show can be just as problematic. Even though these characters come and go, their actions have seen the impact the Gallagher family greatly throughout the rest of the series.

Mickey Beating Up Ian

Mickey looking angry in prison in Shameless

Fans of the show have watched Mickey and Ian's relationship transform over the course of the series. They began seeing each other in secret in their teenage years and ended up getting married, proudly showing their love to everyone. However, even though they end up together, the couple has some moments of trouble that made fans question if they would truly end up together.

This was mainly due to the storyline where Mickey would often abuse Ian, taking his aggression out on him and the store he worked at. This is by far one of the worst things Mickey has done because he failed to see how he had the ability to hurt the people he cared for.

Jimmy Leaving Frank In Canada

Jimmy with his arms crossed in front of the Gallagher house

Jimmy was a character that fans thought would definitely end up with Fiona. He was introduced in season 1 and the two developed a relationship quickly. Jimmy was accepting of Fiona's hectic lifestyle and blended in with the Gallagher family seamlessly until he kidnapped Frank and left him in Canada.

The conman underestimated the Gallagher family's bond with their dad and thought he was doing them a favor by leaving Frank in Canada. He soon learned that the Gallagher family looks out for each other when they worked tirelessly to get Frank back to South Side.

Svetlana Stealing The Bar From Kevin and Veronica

Svetlana at the bar leaning on the counter in Shameless

Svetlana is a character that became an instant fan favorite for her quick comebacks and relationship with Kevin and Veronica. Initially, the three had a great relationship and worked amazingly together at the bar and in raising their children. However, that was until Kevin and Veronica learned that Svetlana had been lying to them throughout the course of their relationship.

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Kevin and Veronica realize that Svetlana has been manipulating their relationship and stealing the bar from them. Svetlana typically did the books for their business and changed the ownership easily. This upset Kevin and Veronica and they ended their relationship. This was by far one of the worst things Svetlana did to people she claimed to care about.

Karen Lying To Lip

Lip and Karen from Shameless Outside a PSAT Testing Centre

Karen was by far one of the more problematic characters on the show. She and Lip became close during her time on the show and casually hooked up from time to time. Karen became pregnant and didn't exactly tell Lip that Timmy could also be the father of the baby. Lip went about and beyond to try to prove to Karen that he would be a good dad. Unfortunately for Lip, he was not the father of Karen's baby and was heartbroken by her lie.

Mandy Running Over Karen

Mandy Looks at Lip in Shameless

Mandy was another love interest of Lip's that appeared early on in the series. Lip tries to keep things casual with Mandy but Mandy clearly develops strong feelings for Lip during her time on the show. After Karen and Lip attempt to make amends, Mandy was seen to become jealous and constructed a plan to get rid of Karen.

Mandy lures Karen to a park in the middle of the night by sending her a message for Lip's phone. When Karen comes out to meet Lip, Mandy runs her over with her car and leaves her in the street. Mandy's ability to angrily lash out and physically hurt people without worrying about consequences makes her character terrifying while also displaying her capability of doing something horrible.

Sheila Marrying Frank Against His Will

Sheila smiling mieschievously

Sheila was a character at the beginning of the Shameless series that was a hilarious addition to the show. She was a homebody with who Frank quickly began a relationship with in order to live in her home. Shelia pushed Frank for a more stable relationship, but Frank was not nearly as interested in Sheila. Sheila longed for family and constantly wanted someone to take care of.

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After Frank becomes extremely ill due to his failing liver, Sheila takes advantage of the situation and marries Frank against his will. Even though Frank did not approve of the marriage, he still moves into her home and lets Sheila take care of him after his time in the hospital.

Sammi Shooting Frank

Sammi Slott at the table with a tea cup in Shameless U.S.

Sammi is the oldest child of Frank from a previous relationship. Frank finds her in an attempt to find an organ donor for himself, and Sammi soon becomes overly attached to Frank. She follows him everywhere he goes and even attempts to get to know her other siblings. Despite trying to cement herself as a member of the Gallagher family, Sammi doesn't ever truly fit in.

Once Frank begins to show signs that he no longer wants Sammi around, she gets extremely upset. Sammi then shoots Frank in the arm, telling him that he does need her to take care of him. Frank realizes that Sammi is dangerous and that he cannot get rid of her. Sammi shooting Frank is one of the worst things that she did during her time on the show because it shows that she capable of hurting people and has no problem doing so to get what she wants.

Jimmy/Steve Lying To The Whole Gallagher Family

An image of Jimmy and Fiona lying on a bed together in Shameless

Despite being a fan favorite, Jimmy is extremely problematic for the entire Gallagher family. When he first begins dating Fiona, Jimmy, going by the name Steve, had been desperately trying to show how well he fits into her life and how capable he is at taking care of her siblings. However, Debbie soon discovers "Steve" is lying to Fiona about who he is and what his name is.

After Jimmy is caught lying, the entire Gallagher family turns on him. Jimmy leaves the country and asks Fiona to join him but she ultimately doesn't show up. He does return later in the series, but he gets caught up in more lies, which only makes him more untrustworthy.

Terry Milkovich Being A Horrible Father

Terry Milkovich answering his door with an angry look on his face

It is no secret to fans of Shameless that the Milkovich family has similar characteristics to the Gallagher family. Both families are problematic and both families have horrible fathers. Terry Milkovich is a terrible father to his children.

He threatens Mickey on multiple occasions because of his sexuality, he impregnated Mandy during a drunken blackout, and he commits crimes without worrying about the consequences. Terry also tries to kill Mickey and Ian on multiple occasions. Terry's actions are horrible, irredeemable, and easily make him one of the worst characters on the show.

NEXT: The Worst Thing Each Main Character Has Done On Shameless