“It was one of the worst experiences I’ve ever had in my life,” Heidi said of her mom's reaction. “There was just no love.”
In May, the Hills star even called the police when her mom "showed up unannounced to my house when she knows I have no interest in seeing or talking with her," Heidi told PEOPLE at the time. "She tore my heart out on national television. She is just trying to create drama in my life."
Now, in a clip from Tuesday's episode of The Hills, Darlene explains to Heidi's sister Holly just how hard she's taking the estrangement.
"I haven't slept in months. I had to go get a prescription for sleeping pills just to be able to go to sleep at night to the point that I didn't even know how I would even make it another day," she says. "I've been mourning the loss of a child and, yeah, it hurts. It hurts more than I thought it could hurt."
The Hills airs Tuesday (10 p.m. EST) on MTV.