McKenzie says she feels caught between her fiancé, Chad, and her identical twin sister, Brittanie. She says that Chad wants her to cut Brittanie out of her life because she’s a drug addict with unpredictable behavior – but McKenzie says she can’t cut off Brittanie because it’s “like losing half of yourself.”

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“He’s in my ear, you know, ‘You need to cut her out. You need to move on with your life and with our family,’” McKenzie tells Dr. Phil on Thursday’s episode. “I just can’t seem to let go.”

“It’s a daily phone call that I dread to even hear the phone ring,” Chad says. “She won’t even talk to Brittanie in the same room as me anymore, because I hear Brittanie’s voice and all’s I hear is, ‘Help me, help me, help me.’ Or, she’s constantly badgering her to do things that McKenzie shouldn’t have to do.”

WATCH: Man Says He Gave Fiancée An Ultimatum: It’s Either Him Or Her Twin Sister

McKenzie says that she hasn’t given her sister money, but she is guilty of paying for cigarettes, shoes, rides and even treatment.

“She plays mom to her,” Chad says.

In the video above, learn more about Brittanie’s behavior, including her history with drugs. Is Brittanie ready to get clean? Hear what she says on Thursday’s episode. Check here to see where you can watch.

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Young Woman Says Twin Sister’s Fiancé Is Driving A Wedge Between Her And Her Sister