I have installed Windows 8 on my Mac. Now, when starting up and selecting Mac, it begins to start, then shuts down I have had Windows 8 installed with bootcamp on my Mac. The disc was partitioned to allow both Mac and Windows to be used.  

When I now go to use MacOS, it begins to start up for a minute then shuts down? The Windows side will start up ok.

When I boot the machine, I have 3 options: 


Mac 
Windows
Recovery


First, why it this happening? Second, unable to boot to Mac OS X and thus unable to start Boot-Camp Assistant how may I uninstall Windows?
I did something similar and ended up incidentally tweaking the partition table from inside of windows. Because of that it wrecked the EFI and GUID and nearly bricked me completely I thought. Start the computer and hit command-r and you should be able to tell where to go from there. I have to warn you though its probably going to involve wiping one or both partitions. If the EFI table has been altered you're going to have to wipe and clean install to get it back to normal working conditions. Hopefully you can just verify and repair your disk though and that'll do the trick.