Robert says ever since he started dating his wife, Caitlin, in 2000, their relationship has been filled with fighting.

“Caitlin is controlling, dramatic and violent,” Robert says. “Caitlin is always holding things over my head and guilt-tripping me.”

TELL DR. PHIL YOUR STORY: Marriage on the rocks?

However, Caitlin claims Robert is a “sad, angry, manipulative, aggressive, vindictive guy,” who has been “verbally abusive to her” since they met. She also claims he has physically hurt her.

“Rob has threatened to kill me many, many times,” she claims.

WATCH: Woman Claims Husband Has Been ‘Verbally Abusive’ Since They Met 16 Years Ago

In the video above from Monday’s episode of Dr. Phil, Dr. Phil asks Robert about a time he admittedly threatened to kill his wife.

"How does it go from, ‘You annoy me,’ to ‘I’m going to put a pickaxe in your head’?” he asks.

“It’s like flipping a switch, sometimes,” Robert says. “It just overwhelms me, comes over me and I act out in anger.”

WATCH: Man Says Wife Antagonizes Him To ‘Get The Reactions Out Of Me’

Watch more in the video above and hear how Caitlin has acted out toward Robert. On Monday’s episode, hear how Caitlin and Robert’s two young children react to their parents fighting. And, see what Dr. Phil tells the couple what they must do for the sake of themselves and their children. Check here to see where you can watch.

TELL DR. PHIL YOUR STORY: Life in crisis?

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