Why Snape turned

[justcarol67]

No: HPFGUIDX 159750

Nikkalmati wrote:
<snip>

>  After they were married, SS could have joined Voldemort, because
his  only friends were there, he was in despair over losing Lily etc.
 The  marriage was in June after graduation let's say.  That fall he
overheard  the prophesy and reported it to LV. When then did he feel
remorse over LV's  plan?  Well, LV could have announced his intent the
next July, when Harry  and Neville were born. July 1980?  That means
SS would have spied for  DD from the time Harry was born until the
Halloween after Harry was a year old,  - for over a year.  On the
other hand, LV could have waited until  shortly before he acted to let
SS  and the DE know his plan.  In that case  SS, would have gone to DD
shortly before he was hired as a teacher, say  July 1981.  <snip>

Carol responds:
I'm also behind in responding to posts (and I also managed somehow to
delete some offlist messages from HPfGU members and admin.--List
Elves, dears, if it was a Howler, could you please resend?). I don't
want to get into the complex question of Snape's motives, which IMO
could involve both the life debt to James and concern for Lily and her
unborn child, with the death of Regulus Black as added incentive (a
revelation of how ruthless the DEs really were, perhaps).

I just want to say that I agree that young Snape would have been hired
around July of 1981 (don't the booklists usually come out then, and DD
would have advertised for a new DADA teacher, the post for which Snape
was applying, around the end of June?), but I think your first guess
at the timing is more likely than the second to be accurate. After
all, Snape spied for Dumbledore "at great personal risk," which
implies a fairly extended period, not just a month or two, and his
spying on Voldemort would have begun just after Harry's birth on July
31, 1980, effectually ended when he began teaching at Hogwarts on
September 1, 1981, some thirteen months later. 

I'm not sure why Dumbledore waited so long to try to persuade the
Potters to use the Fidelius Charm or how Snape, who was at Hogwarts,
could have known that they were in danger at that point (though how
else could Dumbledore have known)?

Carol, still sure that Snape is DDM and that he was nowhere near
Godrics Hollow when LV fell, but confused on a number of points