That Twilight Sparkle.. she always was a little bit sneaky. This is a really well written, but older one. Not for the weak of stomach or feint of heart.
Once you finish this, be sure to check out RECONNECTION, the second part of the Severing series.
Here is the EPILOGUE for the Severing. The grammar is a bit off near the middle but It does make things a little more clear.
Links to the actual archived ones, since each page is shrunk for blogger