"I am truly sorry for the mistakes I have made and for the pain I've caused my family," the 47-year-old actor tells E! News in a statement. "I take full responsibility for my actions and have voluntarily checked myself into a treatment center to address some health and personal issues. I am grateful to be getting the help I need so I can become the husband and father my family deserves."
Just several days ago, on Jan. 18, McDermott was spotted walking out of a local L.A. rehab facility before hopping into a car and leaving.
McDermott's rehab entry comes about one month after reports surfaced claiming that he cheated on Spelling with a 28-year-old woman he met in Toronto. Right after the reports surfaced, the 40-year-old actress took to her blog to gush over McDermott and her supposedly happy family.
"I wanted to take a minute to wish each and every one of you a very Merry Christmas, and for those of you who don't celebrate Christmas, a very happy holiday season!" she wrote. "As another year comes to a close, I can't help but feel so grateful for all of my blessings. My beautiful family, my amazing friends, and of course, all of you!"
Since then, McDermott and Spelling were spotted together in early January leaving what appeared to be McDermott's rehab building. They appeared to be fine with smiles on their faces.
As for the cheating drama, a source told E! News of Spelling, "It's very raw for her right now—she's focusing on the kids."
The couple has four kids, Liam, 6, Stella, 5, Hattie, 2, and Finn, 1.
People first broke the story.