How long can I store homemade caramel or butterscotch sauce?
This similar (also has heavy cream) recipe from epicurious recommends: "Room temperature, up to 3 days; refrigerated, at least 3 months."

http://www.epicurious.com/recipes/food/views/Caramel-Sauce-105889

...And that conforms to my personal opinion, as well. I would not freeze it.