If Trump loses clearly by a landslide in the electoral college than no.
If Trump loses unfairly by electors defecting, I'd be open to still supporting him.
The Electoral College is how we elect Presidents. For better or for worse. The Founders didn't intend electors to necessarily be pledged, and were likely fine with the idea of Faithless Electors to protect America from someone whom, after election, was revealed to be a Napoleon (or a Hitler or a Stalin). Of course that can be "abused", but this is our system. If we wish to elect Presidents by popular vote, we need to amend our Constitution to bring this on.