In a statement on his official Facebook page, Rosberg added: "When I won the race in Suzuka, from the moment when the destiny of the title was in my own hands, the big pressure started and I began to think about ending my racing career if I became World Champion".
Rosberg said that he had nearly made the decision by the morning of the season-ending Abu Dhabi race and that the process had cleared his head.
Lewis Hamilton says it "doesn't matter" who Mercedes choose to replace the recently retired Nico Rosberg.
Rosberg's father, Keke, the 1982 F1 champion, said after watching his son in Abu Dhabi that the strain of fighting Hamilton was sapping him.
"Since 25 years in racing, it has been my dream, my "one thing" to become Formula One World Champion".
Asked who he would like to see alongside him at Mercedes in 2017, an unfazed Hamilton replied: "It doesn't matter who.I'll race them, I'm here to race".
I pushed like insane in every area after the disappointments of the last two years; they fuelled my motivation to levels I had never experienced before.
"The only thing that makes this decision in any way hard for me is because I am putting my racing family into a tough situation". He is the 12th on the all-time Grand Prix winners list. "This season, I tell you, it was so d*** tough. And of course that had an impact on the ones I love, too - it was a whole family effort of sacrifice, putting everything behind our target".
"I can not find enough words to thank my wife Vivian; she has been incredible".
We look back at Nico Rosberg's reaction to being thrown his hat before Lewis Hamilton's podium celebrations at the USA GP in 2015.
"I'm probably one of the only people that it was not a surprise to", he said.
The new world champion's nine victories represented his best-ever tally from a single season and he rates the Singapore GP weekend in September as his standout performance of the year.
Upon informing Toto Wolff, Rosberg says the Mercedes team boss "knew straight away that I was completely convinced and that reassured me".
"We will take the necessary time to evaluate our options and then find the right path for our future".