Caitlin says she thought she had a good relationship with her husband, Robert’s, mom until she claims she did the unthinkable. Caitlin says when Robert moved in with his parents last year to attend school to make a better life for their family, he had an affair -- and his mother let the other woman move into her house and live with them.

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“Her response to me was, ‘He was in love. What’s a mother to do?’” Caitlin says. “I don’t know if I was more mad at him for doing what he did or Susan for allowing it to go on in her house.”

“Caitlin blamed me for Robert having an affair, which wasn’t my fault,” says Susan, Robert’s mother. “I didn’t make him go have an affair. It’s not like we went out and found Robert a girlfriend and brought her to our house.”

WATCH: Man Describes Incident With Wife When He Says He Acted Out In Anger

Caitlin and Robert have been dating since 2000 and married for seven years. The parents of two young children both admit that their relationship has been filled with fighting and they both can get caught up in their anger. Hear more from them and their mothers in the video above.

On Monday’s episode of Dr. Phil, hear what Dr. Phil says they need to do if they want to have a chance to make this marriage work and what they must do for their children. Check here to see where you can watch.

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