Stephen is an aspiring model who claims his parents, Steve and Christine, have physically, mentally and verbally abused him since he was a child – accusations which his parents completely deny.

Stephen, now 20, even claims his mother stood by and watched as his father choked him as a child.

“My mother watched every second and didn’t do a damn thing,” Stephen claims.

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However, Steve and Christine say their son is simply a liar.

“He’s lying about all the abuse that happened,” his mom says. “He wasn’t even spanked as a child.”

Stephen’s girlfriend, Melissa, claims she has witnessed Stephen’s parents be verbally and mentally abusive toward him.

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“From the beginning of my relationship with Stephen, I tried to give his parents the benefit of the doubt,” Melissa says. “As I began to hang out with him more and be around his family, I could see the way that they constantly disrespected him and insulted him. I instantly lost respect for them.”

However, Steve and Christine say they think Melissa may be behind all of the accusations, and may be as “mentally ill” as their son.

“Melissa is very manipulative, controlling and insecure,” Christine says. “She has driven a wedge between his family and all of his friends.”

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“She is actually manipulating the manipulator,” she adds.

In the video above, Melissa discusses her relationship with Stephen’s parents, and explains why she thinks his mom called her a “gold digger.”

This episode of Dr. Phil airs Wednesday.