I think I'm in some serious trouble here. I haven't been using my Mac for about a week and when I needed to do homework I used my bootcamp of windows 7. Today I tried to load up to my Macintosh HD and when I turn it on it stays on the apple logo screen for a second then under the apple logo it shows a status bar and it stays for about a minute(without it even doing anything) then goes away and then I'm stuck on the loading screen. I held down the option key and went to Recovery HD and when I try to reinstall lion I cant even select the hard drive to install it like its not even there. When I go to the disk utility and select Macintosh HD to repair it(for some reason the text is grated out). Then when I try to repair it it tells me "the volume Macintosh HD cannot be repaired" then it says "Error: Disk utility can't repair this disk, reformat the disk and back up files." I hope this is not my only option left. I don't have any time machine backups or anything like that. Is there any other possible way to fix this?