Did you hear a peculiar whooshing and bleeping noise at one point during the night?
If yes, then it was the extraterrestrial aliens playing with your system, attempting to connect to their home planet. If no, then I would suggest that you just document your recent system problems under the heading of "One of Life's Little Mysteries".
In all honesty, I don't think we will be able to explain your recent experience. It could be due to a transient spike on the mains supply or a sub-atomic particle interacting with one of the semiconducting devices in the Billion modem/router or on the RealTek controller card.