Friends and family of the Loose Women star - who has suffered from severe depression, alcoholism and drug addiction throughout her life - are allegedly concerned that her constant feuding with housemate Michael Madsen is starting to take its toll.
"To say Denise is struggling would be an understatement," a source noted to the Daily Star. "She's in tears every night - it only takes something small to set her off. Michael only has to comment and she flips. The other housemates don't know what to do."
A close friend added: "Denise has had depression in the past and everyone is worried a pressurised environment like Big Brother could cause her serious problems.
"It's obvious every day is a struggle for her. It's touch and go if she'll make it to the end of the week."
Celebrity Big Brother evictee Georgia Salpa said while in the house that she believed Welch was "crumbling" under pressure.
Welch also shocked her co-stars by stripping off for a jacuzzi session with 19-year-old Frankie Cocozza.