The 62-year-old lost his daughter Peaches on April 7, and the family held a private funeral service for her on Easter Monday.
But apparently Bob remains stricken with pain, as he regrets not having the opportunity to profess his love for Peaches before she passed.
“He wishes he had got to tell her how much he loved her. It has been very distressing to watch his pain,” a source told UK newspaper The Sun.
Peaches, who was found dead at the age of 25 in her Kent, England home, leaves behind her S.C.U.M rocker husband Tom Cohen and their two young sons Astala, two, and Phaedra, 11 months.
It is claimed Bob is committed to being around his grandchildren more than ever now that their mother is gone.
“Bob is determined they will grow up with a strong family unit around them,” the insider said.
“He will do anything for them and he is rallying all his relatives to never forget them.”
Mourners gathered to celebrate the life of the TV star-and-journalist at the same church where she married rocker Tom in 2012, St Mary Magdalene and St Lawrence Church in Davington, Kent.
The service was held in private, although a host of stars were seen arriving, among them Kate Moss, Sarah Ferguson, Jo Wood, Jools Holland and Jaime Winstone.
The star's death is still unexplained, with a post-mortem proving inconclusive and toxicology tests due back in a few weeks.