What does one do for night life in Dover?

Not much, at least from what I know of the town (and I'm relatively familiar with it). There are a couple local restaurants in Dover Plains and maybe you'll find somewhere to eat in Wingdale, but there aren't really any places nearby to get a good drink or congregate with your peers like a mall, a nightclub, anything like that. It's a pretty quiet town all things considered, so one would think that Dover residents generally have to get out of town to find somewhere more worthwhile to hang out.