As for the friendships among the fiercest rivals, I can't say it doesn't exist, but I think it has more to do with being from the same country or growing up closely together more than anything else.
Let's be completely frank: who likes to lose in professional tennis even if it is at the hands of your "friend"? :nono
A year ago there was an interview with Nole in Serbian where he described his relationship with other players on ATP and he said that the atmosphere and the camaraderie is there but there were times where the big 3 didn't talk to each other from time to time; whether it was Roger and Rafa, Rafa and Nole, or Roger and Nole not speaking to each other. It's the nature of the beast. They are all competitive and they want to always win. Also some players deal with losses better than others (we all remember Rafa in 2011; Roger in some matches, Andy yesterday). I am sure that Nole does not feel as gracious as he looks in some of his biggest defeats, I think he forces himself and has trained himself to look upbeat and "happy" for the other party. But I am positively sure that he is never happy when he loses.
Let's be completely frank: who likes to lose in professional tennis even if it is at the hands of your "friend"? :nono
A year ago there was an interview with Nole in Serbian where he described his relationship with other players on ATP and he said that the atmosphere and the camaraderie is there but there were times where the big 3 didn't talk to each other from time to time; whether it was Roger and Rafa, Rafa and Nole, or Roger and Nole not speaking to each other. It's the nature of the beast. They are all competitive and they want to always win. Also some players deal with losses better than others (we all remember Rafa in 2011; Roger in some matches, Andy yesterday). I am sure that Nole does not feel as gracious as he looks in some of his biggest defeats, I think he forces himself and has trained himself to look upbeat and "happy" for the other party. But I am positively sure that he is never happy when he loses.