Help My Galaxy Nexus won't turn on. Please help!

Hello guys, I have a problem.

My Galaxy Nexus won't turn on. I had installed CyanogenMod 11 and ClockworkMod Recovery and I gave it to my sister and she gave it me back broken. I think she erased the whole system because it shows the "Google" logo and won't boot into system. But the problem is that now, Odin doesn't recognize it and I cannot install a new system. I installed the Universal Samsung Drivers and Odin still cannot recognize it. I think that USB Debugging is not enabled as well.
I also tried with the Galaxy Nexus Toolkit program but it says "USB Debugging not enabled".
How can I install a new system?
Please give me a solution, I love this phone and I don't want to throw it away.

Thank you very much.

scary alien

not really so scary
Welcome to our AndroidForums, androidfanatik.

Who is your GNex's carrier? (I'd like to move your thread to the proper all-things-root area for you) to get you the most appropriate help.

I've not used Odin before, only fastboot, but being a Nexus device, you should have recovery options unless you're actually having a hardware issue.