I don't mind riding on the streets at night because there are plenty of streetlights where I live. I still use lights and reflective gear and im very comfortable riding in traffic. I do not like to ride on trails at night, however.

You could get a wind/mag trainer to ride indoors in the winter, or you could take a spin class at the Y or other gym. In the spring, you could work on getting confident riding on the roads, and eventually start commuting to and from work by bike. That's the most efficient way to work cycling into your day. You get to ride your bike and you get to where you need to go, all at the same time.