I know I am probably too late for you; but fresh whipped cream should hold for a coupl of days in the fridge. Sugar does have something to do with it; it give the cream structure, without it the cream would deflate much faster. I would suggest not whipping it too stiff though, you still want it to be creamy and not break apart when you put your spoon through it.

Happy Baking
Mary
http://www.fortheloveofbaking.com