Flashing folder at start up, all recommended troubleshooting has failed

I really hope someone might be able to help with this cause I am getting frustrated beyond belief.

I have a MacBook Pro with Mavericks OS X 10.9. About a week ago it crashed while I was printing, first my desktop went gray while still displaying my desktop folders and froze. I manually shut it off and upon restart I got the flashing folder with a question mark.

so far my steps have been:

Holding shift at start up - the screen stays grey and freezes (doesn't even get as far as the flashing folder)

⌘ + R - continues into internet recovery mode

disk utility - Disk0 and mac OS X base system are available

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  under base system / first aid / verify disk - I get an all green and no repairs are needed

  
  


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  under erase and restore - all options are grayed out

  
  

when closing out of the OS X Utilities window and going into start up disk - no disk is available

Reinstall OS X - I am able to get though licensing agreement and then it stops on selecting the disk to install on because no disk options show up and there is no searching indicator or failed message.

I have taken my hard drive out and placed it in an enclosure where I was able to access and copy the files through the USB on an older laptop that is running Snow Leopard.

As far as I can tell, my hard drive is fine, all the files were available, there are no strange sounds while it is spinning and I am completely at a loss. Please help.

*** EDIT: troubleshooting also includes:

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  holding D during start up and running the extensive hardware test. No problems were detected.

  
  


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  holding command + option + P + R during start up until the starting sound plays twice to reset NVRAM. It went right back to the flashing folder

  
  


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  holding command + S at start up for single-user mode and my laptop doesn't register, it goes straight back to the flashing folder (same with just holding S, though when I looked it up, everywhere else advised command + S).

  
  

Since I am unable to do anything productive in disk utility, is there anything else that anyone thinks might work?