Some graphics cards' drivers when improperly installed prevents you from hibernating,just like you can't get even a hibernate option in the safe mode.
Try reinstalling graphics card drivers and make sure that you have enabled hibernation in the power options.
Also hibernation is prevented if your c drive or the drive in which your windows directory is installed does not have enough space to store the contents of the memory when hibernation is enabled.So make sure you have enough of space in your windows drive and enable hibernation option in the power options.
Also you will see that there will be a hidden system file allocated for storing the memory contents on the hard disk if you have enabled hibernation(hiberfil.sys)
You can find it in the drive where windows directory exists after disabling hide system files and enabling to show hidden files from the folder options.Make sure such a file exists for proper hibernation.