It's always so good to hear from you. How is Harry doing? I haven't seen much of the lad, only the times when I've managed to sneak about.
As for Pettigrew, the reasons you stated for choosing him as Secret Keeper really is as it was. I think everyone saw me as the obvious choice, because I was headstrong and so close to James. Nobody saw that Pettigrew might betray James; he seemed the perfect choice to myself because of his shyness and his ability to fade into a crowd. No one would suspect he was holding that secret. I'm almost sure that Voldemort didn't come after him, but that he went to Voldemort of his own will.
I am also inclined to say that you shouldn't tell Harry about Pettigrew yet. If you're going to tell him about Pettigrew, he'd want to hear the whole story, and you'd have to tell him that you're a werewolf and that I'm an Animagus. I'm not sure that we can trust a 13 year old boy with information like that quite yet; you can't be too sure that he might not let it slip to one of his classmates. But you know him better than I do, obviously, so maybe my advice doesn't apply.
Food is extremely scarce where I am. Sometimes I can manage to dig something up from the rubbish bins as Padfoot, but it's usually nothing more than an apple core or a lettuce head. I was lucky once and found a rabbit's head. So if you can manage to do so, would you mind sending a loaf of bread, or even some cakey pie? Thanks.