SOLVED. Girl and her family trying to survive after the moon comes closer to Earth [s]

[Catherine]

I read this not that long ago --maybe a year-- but I can't remember the title (or author). It was about how a meteorite hits the moon and the moon gets shoved closer to Earth. The tides rise and all that and people drown and everything goes ballistic. This teen girl and her family (mom, big bro, lil' bro (daddy is absent; has a girlfriend)) are rationing their food and just trying to stay alive. At one point lil' bro gets sent off to a baseball camp 'cause they have food there. The girl's one friend starves 'cause she keeps giving her food away (because she's fanatically religious (don't get me wrong; I'm religious, but this was silly)). Another friend of hers leaves to go south or something. Main-character-girl hangs out with a guy from school at a pond (they swim in the summer and she skates in the winter (she's a big fan of some teen boy who's an Olympic ice-skater)). The whole family, if I remember correctly, make it to the end of the book, where someone shows up with a bunch of food.
Oh, they live in Pennsylvania, and all they serve at school are PB 'n J sandwiches. The cover has got the moon on it, and a house in the snow.
And it was written in diary format, pretty sure.

[Elizabeth]

Life As We Knew It

[mdt]

Also has two sequels: The Dead and the Gone and This World We Live In

[Catherine]

It's "Life As We Knew It"! Thanks, so much, you two!