I believe I have a similar issue.

I recently installed updates with my update manager. Later in the day my computer randomly went into hibernation mode & wouldn't come back out of it.

After unsuccessfully trying to get it to come out of hibernating I simply shut it down by holding down the power button.

1. Why I rebooted the first thing I noticed was that I couldn't connect to the internet.
2. Next I noticed that I couldn't detect my local network.
3. I next realized that my computer didn't detect the ethernet cable connected to it.
4. Then I realized my network manager applet was gone, yet it still exists within my file system. Plus I have an Icon on my toolbar that says the network is disabled.

Thus far I have not found a way to get the network to be enabled again. I tried looking at my most recently installed packages and reinstalling them. That doesn't seem to have worked.

No clue what the problem is or why this happened, guessing its from my updates from earlier.

Would appreciate any advice, I'm a bit of a Linux novice, so it would be helpful if you could 'hold my hand' through the steps too. Maybe if you could give me an explanation of why so I can learn, that's only if you have the time or want to. First and foremost I would just like a solution, thanks.