Carlisle, who had spells with the likes of QPR, Leeds United and Burnley, spent six weeks in hospital having been hit by a lorry on the A64 near Bishopthorpe, York, on December 22.
The 35-year-old was seriously hurt in the incident, which came days after he had been charged with drink driving and informed he was set to lose his role as a TV pundit.
In an exclusive interview with The Sun, Carlisle, who has openly discussed suffering from depression in the past, revealed he had deliberately stepped in front of the vehicle that struck him and "wanted to die".
He has since undergone treatment at a psychiatric unit and is now looking forward with renewed optimism.
Carlisle said: "I ventured out of my room [at the psychiatric unit] not as Clarke the ex-footballer, but as Clarke, a mental health patient.
"My road to recovery will be eternal. Today I am excited and I'm confident because I’ve finally been truly diagnosed."
Discussing the injuries he suffered, Carlisle acknowledged how lucky he had been.
"I got a massive cut across my knee and road burns to my face - but I'm still alive," he added.
"The laws of physics dictate that I should have died."
Carlisle's wife Gemma took to Twitter to explain the couple's reasons for revealing the details of Clarke's suicide attempt.
She wrote: "Clarke and I thought very long and hard about this over the last week, and feel that as you all supported us so immensely through this ordeal you deserved the truth.
"We also want to highlight and create understanding for a lot of issues and feel it would be hypocritical of us to saying [sic] nothing.
"I'm hoping we get an honest and fair account that will help others and not one that is sensationalised."
Gemma Carlisle added: "Suicide & depression is not selfish. It's a serious illness where your world & reality are warped.
"We send our love & thoughts to the lorry driver & family. It could have been anyone and Clarke is desperately sorry that it was him."
