A motive for Sirius - clarification

[pippin_999 <foxmoth@qnet.com>]

No: HPFGUIDX 48328

I wrote:
> > The Animagi couldn't have continued to visit the Willow once 
Snape knew about it. 
> > What if the prospect of losing their company drove Lupin to 
despair?  If  Lupin was on the verge of suicide (as troubled teens 
all too often are), could Sirius have seen The Prank as the only 
way to  save his friend? 
> 
> 
Audra:
> 
> I don't know if I understand this correctly.  Sirius says he 
deliberately let 
> the information slip to Snape about the Willow.  Do you mean 
you think Snape  found out about Lupin's secret before that, and 
was going to expose him, and  that's what made Lupin suicidal?  
So *then* Sirius let it slip how to get  into the Willow, hoping 
Snape would follow him and be killed so that Lupin's 
> secret would be safe?
> 

Lupin says, "...anyway, Snape had seen me crossing the 
grounds with Madam Pomfrey as she led me toward the 
Whomping Willow to transform." POA 18.

So if Snape didn't actually see Lupin enter the Willow, he did see 
enough to make him think that Lupin and the Willow were 
connected. He probably saw the branches freeze as Lupin 
entered. And somehow the Marauders discovered that.

 It would be only a matter of time before Snape saw the Animagi 
going out to the tree. The I-Cloak   wouldn't have kept Snape from 
seeing the branches freeze as they were going in or out. There'd 
be a full moon. He'd know something was up. And Snape is very 
good at putting things together.

With Snape watching the willow, it  would be too dangerous for 
the other Marauders to join him for his transformations and 
*that* made Lupin suicidal. So *then* Sirius deliberately let 
Snape know how to enter the willow, hoping that Snape would 
either get killed  or get caught snooping and be warned off. 

Pippin