The 41-year-old former glamour model has apparently reached out to her former hubby after he spoke on his battle with mental health.
Katie, who split from Peter in 2009, believes she can aid the 46-year-old singer because of the traumas she has been through over the years.
According to Closer Magazine, Katie has told friends she is the one to save Pete, despite him being married to qualified doctor Emily, 29.
A source told the publication: "Some friends may think she's deluded, but she's insisting that, while Emily's a doctor, he may not want to talk to her about certain things, like their relationship.
"She's adamant she's the only person who can help."
Ent Daily has contacted representatives for Katie for comment.Katie spent time in rehab facility The Priory last year. She checked in to deal with her PTSD (Post Traumatic Stress Disorder).
As well as coming to terms with her ex Kieran Hayler's multiple cheating, she has also had to deal with nearly going bankrupt and her mum Amy's terminal illness.
The Closer insider added: "After everything she's been through, she's always seen herself as a bit of a life guru. Katie sent him a heartfelt message saying she'd like to help, advising him to consider a rehab stint, saying it helped clear her thoughts."
She's adamant she's the only person who can help.
Peter, who has Junior, 14, and Princess, 11, with Katie, has been struggling with anxiety and panic attacks for years.
He explained: "I got to some very dark points where I remember praying to God, please get me through this day, just to get through one more day. That’s how bad it got."
The star also has five-year-old Amelia and two-year-old Theo with Emily.
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