It was reported last week that the Celebrity Big Brother winner had been having an eight-month affair behind husband Tim Healy's back with party organiser Lincoln Townley.
Welch is said to have continued the fling by spending the night with Townley after filming Loose Women on Monday and met him again the following day at the Landmark Hotel in Marylebone.
"She's clearly a torn woman and finding it all very difficult. She loves Tim dearly and only wants the best for her children, but she can't help her strong feelings for Lincoln. They haven't changed during her time on Celebrity Big Brother," a source told the Sunday Mirror.
"Denise has had a very busy week with her TV commitments after leaving the show but has still found time for Lincoln.
"She is worried her marriage has taken its course, but it's not that simple. When she's in front of her viewers on Loose Women, talking to her fans on the street and playing up for the photographers she makes out that all is fine at home."
Welch had previously insisted that her marriage will survive these latest infidelity claims.
She has openly admitted in the past that both herself and Healy have cheated on one another.