Lewis Hamilton said his second world title felt more important to him than the first he won with McLaren in 2008.
Hamilton said: "It means so much more than the first one - it feels so long. I feel so blessed.
"It has been an incredible year. It feels like an out-of-body experience."
The triumph meant Hamilton becomes only the fourth Briton to win two world titles, moving level with Jim Clark and Graham Hill. He is now one behind Sir Jackie Stewart.
Michael Schumacher is the all-time record holder with seven, while the most successful current driver is Sebastian Vettel on four. Another contemporary, Fernando Alonso, is also on two.
Hamilton, who ended the season with 11 victories compared to Rosberg's five, said he had been faced with difficult emotions throughout race day at Yas Marina.
"It is very hard to soak all this up," he said. "I didn't sleep. I went to bed at 12, woke up 5am, went for a run and thought for sure I would be tired when I got to the race but I felt composed.
"My family came and surprised me at breakfast. I had wanted them to be here but I didn't know if I would be able to give them time. I didn't want to get to the end and say, 'I wish I had done this or that'."
Hamilton's father Anthony, step-mother Linda, brother Nicolas and girlfriend Nicole Scherzinger all flew into Abu Dhabi on Sunday morning to surprise him, and then celebrated with him afterwards.
He was also congratulated on the in-car radio by Prince Harry, who was attending the race.
Hamilton said: "It's really going to take some time to sink in. I don't know what I have next week but I hope to see family.
"At the end of the week we will have seat fitting but I might need a bit of bulking! I don't really drink so will let everyone else get obliterated.
"As a driver you are always conscious of the possibilities of the car failure. It's not something you can prevent. We've had ups and downs and I did not know what was going to happen. But I had so much faith. I knew I could do it. I had faith God would keep it going.
"I had no idea my family and Nicole were coming. I was messaging my dad last night and knew I had to be so selfish and did not want to involve them. But my dad messaged me. I said I wanted them here but either way I knew they would be.
"I did not hear anything Prince Harry said. It was very cool, I'm very grateful. It's unreal, it's incredible."
For the first time, Hamilton admitted that he disliked the idea of double points, which were controversially awarded at the final race of the season for the first time.
Double points meant Hamilton needed to finish second in the final race if Rosberg won it, rather than sixth.
In the post-race news conference, sitting next to Williams driver Felipe Massa, Hamilton said: "Coming to the last race knowing it was double points. Jeez…"
Hamilton then turned to Massa, who he beat to the 2008 title by one point after passing another car at the last corner of the last lap of the last race of the season, and said: "Did you think it was a good idea? I didn't think it was a good idea."
Massa joked: "I think it was a good idea in 2008."