Neither Christy nor Bonnie are perfect, but their on-screen dynamic makes Mom the comedic success that it is. Christy and Bonnie Plunkett's relationship is tumultuous at best, with endearing moments interspersed between tense ones.

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The show had a strong focus on the concept of family, and one recurring theme was the reunion of a family that has been fractured by alcoholism. With drinking being such a scar on both Christy and Bonnie's lives, it's understandable that there are a few bumps on the road to reconciliation. Bonnie see-sawing between being a great mom and a terrible mom doesn't do anything to hasten the smoothing over of both their lives, though.

Great Mom: Supported Christy's Decision To Go To Law School

Mom's Christy in the kitchen.

When Christy started at law school, Bonnie was uncharacteristically kind in the morning, preparing Christy's breakfast cheerfully sending her off. Later in the series, Bonnie is less supportive of Christy's studies, mostly due to not understanding the workload of a law degree.

Of course, Bonnie predominantly looks out for herself, and she capitalizes on Christy's law student status for her own benefit, using Christy as her legal defense when the tax office raised some questions. However, Bonnie's initially supportive behavior is heartwarming, even if she does return to her selfish ways later.

Awful Mom: She Hid $4000 From Christy

Bonnie pretends to be smoking on Mom.

When Bonnie asks to stay with Christy, the naive Christy allows her to do so, though her kindness makes her one of Mom's most relatable characters. Christy's house is already full with her and her two children living there, and Bonnie's presence cramps the household even more. When Christy discovers that Bonnie has $4000 in cash stashed away and could have easily paid some rent or even got her own home, Christy is angry.

The secret cash stash paves the way for a heart-to-heart conversation about secrets, during which Bonnie reveals that Christie's aunt Janine was not her aunt and that she was actually Bonnie's lover. Bonnie did Christy wrong by pretending to be too broke to contribute to the household expenses. Lying about Janine's role in their lives wasn't model-mother behavior, either.

Great Mom: Supported Christy When She Dumped Dave

David holds Christy's hand while at her work.

David and Christy seemed to be one of television's most perfect sitcom couples. Unfortunately, David is also a problem drinker and has substance abuse problems. As her infatuation with David increases, Christy begins to skip days of work, and she soon finds her own sobriety in question. "You know what's crazy," she tells Bonnie. "The more I'm with him, the more I want to throw my sobriety out the window."

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When David's behavior intensifies, it becomes apparent that, although David is intelligent, he has no intention of trying to get his substance abuse problems under control. Christy makes the decision to dump him. "You're doing the right thing," Bonnie tells Christy. "Don't worry," she continues, obviously lying, "There will be other hot, smart, freshly exfoliated firemen."

Awful Mom: Trashed A Wedding Dress Store

Bonnie and Christy fight on the floor of a wedding dress store.

While trying to show up Bonnie, Christy says that she will pay for Violet's wedding dress. As Violet rushes off to try on the gown, Christie says to Bonnie, "thanks a lot! Now I'm on the hook for a dress I can't afford." Christie accuses Bonnie of ruining her daughter's wedding day, but Bonnie retorts that the day will be ruined when Christy's credit card is declined.

Christy tackles Bonnie, and soon the racks of dresses and all the display items are sent flying. The fight ends when a distraught Violet emerges from the dressing room, horrified. What should have been one of the most heartwarming moments on the show turns into a humiliating disaster.

Great Mom: Defended Christy's Reputation At Alvin's Funeral

Bonnie and Christy at Alvin's Funeral in Mom.

When the eulogist at Alvin's funeral doesn't mention Christy as a dependent, Bonnie interrupts the speaker to point out that Alvin was Christy's father, also, and the entire room full of mourners, including Alvin's estranged wife, Lorraine, turns to stare. Christy buries her face in her hands, but Bonnie refuses to be shamed.

Lorraine's bitterness seeps into her words when she takes the podium."[Alvin] made some mistakes," Lorraine says. Glaring at Bonnie, she adds, "two of whom are here today." Bonnie doesn't even bother to hear Lorraine out and takes the podium, delivering a touching eulogy of her own. Bonnie's refusal to allow Christy's significance to be ignored makes her a great mother.

Awful Mom: She Slept With One Of Christy's Coworkers

Bonnie out on a date with Chef Rudy on Mom.

When Bonnie goes on a date with Christy's sleazy coworker Chef Rudy, things go well. However, he soon tires of her and tries to ditch her. Chef Rudy returns home one evening to find Bonnie waiting in his apartment. She tells him that she wants to hurt him emotionally, just as he hurt her.

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Bonnie smashing vintage bottles of wine with a bat while Chef Rudy falls to his knees has gone down as part of one of the funniest episodes of Mom. However, Bonnie's bad behavior was unlikely to be overlooked when Chef Rudy and Bonnie finally parted ways for good and could have hurt Christy in the future.

Great Mom: Got Through Christmas Day Alone With A Newborn Baby

Bonnie speaking at an AA meeting.

Christy was born on Christmas Eve. What should have been an especially sentimental Christmas holiday turned to disaster when Bonnie became aware that Alvin had abandoned her and newborn Christy. When Alvin does resurface decades later, it's understandable that Bonnie still harbors a lot of anger towards him and is wary of Christy getting to know him.

Christmas time likely always reminded Bonnie of the abandonment, and it's not the kind of thing that is easily forgotten nor forgiven. In a later episode, Bonnie and Christy are robbed at Christmas time, so it seems as though Christy and Bonnie don't often get to see happy Christmases.

Awful Mom: Didn't Support Christy When Jill Was Angry With Her

Christy introducing Jill on the sitcom Mom.

Spoiled Jill's expectations of what it's like to be a parent are wildly unrealistic. Jill thinks that having a child will be like having a new toy poodle to play with. When Christy honestly says that she doesn't think Jill will be a good parent, Jill is offended and gives Christy the cold shoulder.

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While it's understandable that Jill would feel personally attacked by Christy's comment, what's not understandable is why Bonnie would allow Jill to be openly rude to Christy. After one tense lunch, Christy asks Bonnie if she thinks that Jill will be a good mother. Bonnie says no, but she adds that she wouldn't say it to her face, only behind her back. In this instance, Bonnie isn't just an unsupportive mother, but a two-faced friend, as well.

Great Mom: Made It Clear To Her Ex That He Must Respect His Daughter

Bonnie out on a date with Alvin on Mom.

Bonnie is still furious with Alvin when he re-enters her life. "You left me with a one-day-old baby and $18 in my jeans," she yells at him, before telling him that he hurt her in a way that nobody else ever could. The pain that Bonnie has been bottling up since Christy's birth comes tumbling out.

She went on to say that if Alvin hurt Christy, he would be answering to Bonnie. Alvin heeded the message carefully, leaning back in his seat to keep as far away from volatile Bonnie as possible. Bonnie may not be the perfect mother, but she can be fiercely protective of Christy when the need arises.

Awful Mom: She Ruined Christy's Wedding

A bloody Bonnie talks directly to a camera at Christy's wedding.

When Adam is skeptical that Bonnie can be any wilder than she already is, Bonnie puts on the video of Christy's disastrous wedding. Bonnie, drunk, is shown grinding against another guest's leg, having pushed the man's girlfriend away. When the video cuts to the bouquet toss, Bonnie aggressively tackles the other women, emerging later with a bloodied face, but triumphantly bearing the bouquet.

Later in the video, a tearful Christie apologizes to her guests while Bonnie is forcibly escorted out of the venue by two police officers. "I had to punch him!" Bonnie yells. "He stole my cupcake!" Ruining Christie's wedding is easily one of the worst things that Bonnie has ever done to Christy.

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