There's no winning in Syria. But the question of whether the West can work with Assad is becoming more of a reality now that we have President-elect Donald Trump in the United States.
Donald Trump's view during his presidential campaign was quite clear: he said the US's current policies are far worse than supporting Assad. He says that the U.S. is providing billions of dollars worth of hardware and equipment to rebel groups, and other armed groups he says are dangerous. His argument is that we don't actually know what these groups will do with that support, if Assad falls.
“Trump has inferred that he would strengthen Assad and work with Vladimir Putin.”
What he's inferred is that he would possibly support strengthening Assad and perhaps even going as far as working with the Russian president Vladimir Putin, who's been supporting Assad with his airstrikes against anti-Assad rebels.
Therefore we could see this new Trump administration walk alongside Russia, paving the way for Assad to reassert himself as the leader of all of Syria, and to crack down on the rebellion which has led to the current horror show.