Writing in the Sun he praised the bravery of his wife Rebecca Ellison, who died aged 34 earlier this month.
The QPR defender also said he “felt guilty” missing games for his side while they tried to avoid relegation.
His wife, whom he married in 2009, died on 1 May from breast cancer.
She leaves behind three children; Lorenz, nine, Tate, six, and four-year-old Tia.
‘Fighting for her life’
In his article Ferdinand reveals how his wife’s illness led to her being permanently hospitalised and “normality then became impossible”.
He writes: “As footballers, we often talk about missing important games through injury as if it was the end of the world.
“Believe me, it isn’t when compared to your wife and mother of your children dying of cancer at the age of 34.
“Rebecca was an incredibly brave woman and a very private person who didn’t want anything about her illness to appear in the media while she was fighting for her life. Only a close-knit group of family and friends knew.”
As the illness took hold Ferdinand said he told his manager to “take him out of the equation completely” when it came to choosing his side.
He adds: “I wanted to carry on for the team but I couldn’t make any promises and it wasn’t fair on the boss wondering whether I was available or not.
“I admit I felt guilty that I was letting the club down in our relegation fight.
“None of the lads knew what was going on because I didn’t tell them. But eventually I asked the medical staff to let the other players know.”
Since the death fellow players of the game have offered their condolences to Ferdinand including striker Leroy Fer who after scoring a goal against Liverpool revealed a personalised message for the family under his shirt.
Ferdinand adds: “I couldn’t have asked for greater support from QPR. Everyone connected with the club has been fantastic.
“The day it was announced that Rebecca had died, we were overwhelmed by messages of support.
“To hear the fans at Old Trafford and West Ham singing for us and seeing Steven Gerrard hand over flowers to my team-mate Joey Barton was special.”