That's a very difficult question to answer.
From what I've read, Monica could have come back PHYSICALLY in three months. The wound wasn't especially deep. (There is, of course, no such thing a 'shallow' wound when someone is trying to kill you.)
As for the mental aspect of things, who can say? Jenn was one messed up little girl. Perhaps I can best answer the question by posing another one. Who made the greater comeback, basketball player Paul Pierce form being shot, Lance Armstrong from cancer, or Monica from stabbing?
The problem her is that we don't know if Jenn was an addict or a casual drug user. If an addict, I'd have to rate her comeback greater than Monica's.
Proud to be an American
Not blind. Not uninformed. We are party to atrocities. But the response of the world after 9/11 is worth noting. Even our most dire enemies offered aid. We should all be so lucky.