On the nights we go out - Around 6 or so we share a couple cheese plates from room service and enjoy them with our wine on our balcony. Then it's time to get ready for dinner. Dinner generally starts anywhere from 7:30 to 8:30. If the timing is right we'll catch sunset by the seaview pool with another adult beverage. One of the advantages of not being a regular cruiser is that whatever is on the main stage is probably something we haven't seen before! So we'll go to the show and then find some music (70's or later please!). Most likely back to the cabin by midnight, earlier if there is port day the next day.
We do not do this every night. We really don't have the desire to go "out" every night on a cruise. We are much more likely to do land trips and when we do, we don't go out every night for the weeks that we're traveling. It's no different on a cruise.