Jeremiah says in the last year, his girlfriend, Danielle, has gone from being very active and the life of the party, to withdrawn, angry and moody.

TELL DR. PHIL YOUR STORY: Fed up with your spouse?

“I miss the old Danielle. We used to be two peas in a pod,” he says. “Now, we argue more than we ever did because of her short fuse, because of her anxiety. It seems like anything I say will set her off.”

WATCH: Woman Insists There’s Something Seriously Wrong With Her And Doctors Just Can’t Determine What It Is

Jeremiah says he blames Danielle’s anxiety for the change in her behavior and fears that she’s never going to get better. “I’m afraid that nothing’s going to change,” he says. “I’m supportive, but there’s only so much I can take.”

Hear more of their story in the video above, including why Danielle says she sometimes doesn't follow doctors' treatment protocol. Is Danielle really sick? Have doctors just missed the underlying cause of all her problems? See what Dr. Phil thinks may be causing her anxiety on Friday’s episode. Check here to see where you can watch.

TELL DR. PHIL YOUR STORY: Is Dr. Phil your only hope?

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