Patients on 'Celebrity Rehab with Dr. Drew' (Sundays, 10PM on VH1) tend to have more than their fair share of rocky relationships. That's especially true of Michael Lohan, who had an explosive blow-up with his ex-fiance Kate Major, who he and Dr. Drew have been trying to convince to enter treatment.

The incident started when Lohan appeared in a tabloid report kissing Kim Granatell, better known as Kim G from 'The Real Housewives of New Jersey.' That sent Major, who was on her way to the Pasadena Recovery Center for visiting day, into a fit, which soon escalated into a phone shouting match. Lohan worked himself into a rage while denying that he kissed Kim G., and threatened to leave rehab as he was being told he needed to calm down because of his heart.

"Everything is going in the garbage now because of you," Lohan shouted into the phone. "If I walk out this door, they're chasing me. Are you coming, are you coming here or am I walking out? You tell me right now. Right now, or I will be at that apartment tonight. You're killing, you are killing me."

When Major did show up, things got worse. "I'm not even attracted to you," she screamed. "You're old, you're ugly, and you're bald." Lohan wound up in handcuffs for reasons that weren't entirely clear. It was the most explosive incident 'Celebrity Rehab' seen since ... last week, when Amy Fischer's husband threatened to kill Jeremy Jackson.