Interesting note that the book was fake which means that who he was going to be with really has never changed; the whole destined girl kinda rings a bell doesn't it; well in any case i really can only see a few possibilities for the series
1.The series ends
2.The series takes a time skip (i doubt it will 100 years though, as it wouldn't be the same with the known cast)
3.Some error occurs with the process and Asuna doesn't freeze at all.
I personally think it will be 2 but that's just me; 3 also seems likely because i just don't see it ending considering the still haven't solved the whole encounter with Nagi and what he meant by killing him would end everything. I picture a few more chapters like this, maybe 2-3 then we get our scenario; also people who think it will end do you really think this is conclusive? i mean lets say it ended next chapter; they would have to explain if the plan was a success, what happened to Asuna, Negi and such, the lifemaker. While i don't think they should drag it out, it still has a bit to go in my opinion before we have the final ending.