The TV presenter described herself as feeling "sick and overwhelmed" when her two-year-old son Valentino was diagnosed with autism eight years ago, and shared candid entries from her diary in 2007 with her audience:
"I want to run so far away from the house tonight and scream from the rooftops. I am unhappy, somebody save me," she read.
"I want to throw the towel in and wave a white flag. I desperately want to fold in my hand of cards. I've had enough – children, marriage, life, work, the lot, it's too hard to handle and I can't cope."
The 44-year-old is mother to Tino, 10, and 12-year-old Roman from her marriage to actor Daniel Caltagirone, whom she split from in 2009.
She describes how Roman was more verbal, and that Tino would sit and stare blankly into space, and how she felt as though they had disconnected, and she did not know how what her son needed or wanted, they had "lost each other".
The former I'm A Celebrity contestant told the audience how she overcame this when her son's behaviour began to change after she began to understand her son's needs.
She proudly says how Tino, now 10 years old, is now thriving after his therapy sessions, and continue to put the skills they've learned to good use.
Autism is a condition that affects social interaction, communication, interests and behaviour. The effects typically develop in childhood, though the impact of these may not be apparent until there is a significant change in the person's life, such as a change of school.
Mark Lever, Chief Executive of the National Autistic Society, said that over 1-in-100 people are on the autism spectrum and can have a profound effect on those close to them, but support at the right time can make a big difference.
"Melanie has bravely revealed that a diagnosis can also be very emotional and leave families feeling isolated. This is why it's so important that professionals making the diagnosis make sure that adults and children know exactly what to expect as well as where they can go for advice and support," he said.
Jenny McCarthy and Toni Braxton are two other celebrity mothers who have children with autism. They both speak openly about the importance of early intervention to help in the development of their autistic children. Celebrity dads with children who are on the autistic spectrum include Boyzone's Keith Duffy, Sylvester Stallone, and John Travolta.