Why does DD trust Snape? (Re: Snapes Behaviour and Legimens)

[Chris Tredennick]

No: HPFGUIDX 161907

> Sydney:
<snip>
> http://whysnape.tripod.com/rickmanfrench.htm ..

> Q: We gradually discover what Snape went through in the past. It seems
> he didn't have it easy as a teenager...
>
> -[Alan] He wasn't very sociable either.  Snape never had friends. Lily
> Potter really tried to be nice with him, but Snape couldn't support
> her pity.  And with James Potter, his best mate Sirius Black and their
> partner in crime Lupin spending their time ridiculing him, he shut
> himself in even more.  Snape's life is much more complex than it
> seems.  He was a member of the Death Eaters and then became a turncoat
> to join Dumbledore' side. But his past keeps clinging onto him,  so
> coupled with his demeanor few trust him.

I'm sure this topic has been beaten to death, but I have searched for
a recent thread on Snape's loyalty and haven't found one so I'd like
to start a fresh discussion using some bits of information from the
aforementioned interview.
I have been working on a theory regarding the reason DD trusts Snape
"completely".  I believe it has something to do with love,
specifically love Snape has/had for Lily.  The theory is such: Lily
was one of the only people trying to be nice to Snape.  He accepted
this companion at first.  His attachment grew into a love for her.
Maybe he told her he loved her maybe not, but eventually he decided
that his love would never be returned and so began to show animosity
toward her.  Later, when he tells LV the prophecy and finds that LV
means to kill the Potters, he intercedes on Lily's behalf (he still
loves her).  When she dies, Snape is exceptionally remorseful and
approaches DD to redeem himself.  DD is convinced of Snapes affection
for Lily and for this reason chooses to believe Snape is DDM.
I use two main arguments for this theory:
1) DD is a wizard well-versed in the magic of love.  It would be easy
for such a wizard to find the true nature of Snape's feelings.  LV
despises love; it would be easy for an accomplished Legilimens (Snape)
to disguise his feelings (love) from LV who underestimates its power.

2) Snape's Worst Memory.  It struck me as odd that Snape's worst
memory would be him being picked on by James/Sirius.  Didn't that
happen all the time?  Why was this one the worst?  I think it is
because this time Snape lashes aggressively at Lily when she tries to
help him.  Possibly ending what little 'friendship' they had.

Also, a number of small items hint at this theory:
- Lily and Snape were both excellent at potions.  It is likely they
were in the same classes and possibly studied/worked together.
- Lily "needn't have died," it is presumed that only a loyal Death
Eater could have convinced LV not to kill Lily.  Snape was certainly
in the 'inner circle.'
- Snape continues to save/help Harry when he outwardly shows
animosity.  It is possible that this is because of his life-debt to
James, his act for DD, and possibly because he sees Lily sometimes
when he looks at Harry.

I would appreciate feedback on this theory.  Happy Thanksgiving to
those in the US!

Chris