Kakashi lost many of his friends and all of his family in his tragic past, so he tends to be a bit of a loner. However, he does have a few people that could be considered his friends. He seems to be kind of close to Iruka, Jiraya, the third and fifth Hokages, and, of course, Team 7. He is also quite close to Might Guy, though they are technically rivals (more on Guy's part than Kakashi's!).
Sorry if I missed any obvious ones. :)
Not really an enemy more as a person he competes with daily to surpass, and the answer to that is his friend Might Guy
His face
Grey or White.
kakashi chronicles
No, she is dead.
Yes she is dead, but noone knows how.
No. It is not shown in the movie
september 15
Kakashi's full name is : Hetake, Kakashi
She's unkown, but it's stated in the manga that she died very young.
Sakumo Hatake (or Hatake Sakumo) is Kakashi's father.
She is dead, but noone knows how she died.