Tonks in HBP ( spoilers of course!)

[kjirstem]

No: HPFGUIDX 132970

I love Remus/Tonks together and individually, but I'm not yet
ready to believe all is as it appears.  I may be entirely too
suspicious, but for much of the book I was convinced that Tonks was
someone else on Polyjuice.   I don't want that to be the case but
I'm not completely convinced because depression due to Lupin-loss
doesn't answer some of my concerns.  

There are a lot of strange things happening with Tonks in HBP.  Some
are:

- Clumsiness lost? (jumps off Hogwart's Express w/o trouble)
- Metamorph abilities MIA until the end
- Patronus changes appearance
- Different conversational style with Harry
- Extreme reaction to Sirius' death
- She's in the habit of strolling the Room of Req't corridor
- She's ineffective in the battle below the Astronomy tower

Many of these are explained away by 1) her sorrow over Sirius'
death and 2) depression due to Lupin's rejection of her.  However,
that doesn't explain the last two points on the list, so I'll
elaborate a bit on those.
 
Tonks in the Room of Req't corridor:
In Chapter 21, page 465 (US Deluxe ed), Tonks strolls down the
corridor that the Room of Requirement is off, 

"There, to his utter astonishment, was Tonks, walking toward him
as though she frequently strolled up this corridor."  

Harry is surprised to see her there and questions what she is doing. 
The answers are not entirely sensible, including things like looking
for Dumbledore and the topic changes with Tonks asking for
information, then Tonks leaves the same way she came.  

Frankly, what is Tonks doing in that corridor?  The conversation
serves no apparent purpose, except to establish that Tonks is in the
habit of passing the Room of Requirement.  Seems like mostly baddies
and Harry are the ones who haunt that corridor. 

Tonks in the battle below the Astronomy tower:
When Harry descends from the Astronomy tower, he comes upon the battle
between Order members and DE.  Part of that battle is Tonks fighting 

"
an enormous blond wizard who was sending curses flying in all
directions, so that they ricocheted off the walls around them,
cracking stone, shattering the nearest window -- ".  (US Deluxe ed, p
599)

Harry hexes the blond guy to get rid of the chaos and blondie runs
off, why was Tonks unable to do this on her own?  Why isn't
blondie actually attacking Tonks?

These two incidents are enough to make me question if something other
than depression is affecting Tonks.  Tonks could be ESE and a Death
Eater herself, but it seems a stretch for a half-blood. (Though,
obviously she wouldn't be the first.)  I think it is more likely
that we have Polyjuiced!Tonks running around.   Possibly after
Dumbledore's death the real Tonks was Obliviated and returned.  

There are a couple things that I think support this idea.  For one,
Tonks mother is Andromeda, Sirius' favorite cousin.  I would
expect Andromeda to be sadder about Sirius' death than Tonks. 
With Andromeda (who was probably a Slytherin) as a mother it is 
likely that Tonks is more exposed to attack by family members than
some other Order members.  Quite possibly Andromeda is the one who 
is assuming Tonk's form, perhaps under duress from other family
members (eg. Bellatrix, Narcissa).  

Ah, so, let the tomato tossing begin
at least they are in season.
kjirstem