I have been using VMWare Fusion on my Mac for the past three years. About a year and a half ago, my Mac began to fail when waking from sleep mode. After a few failures, I noticed it only happened if I left a Virtual Machine running when putting the Mac to sleep.
Eversince, I have been pausing my VM each time I put my Mac to sleep. Every now and again, I would search the web for solutions. Just this weekend, I stumbled upon a StackExchange question with a simple solution.
Here is the culprit:
I have been testing it over the last few days and, so far, my Mac has not failed to return from sleep.