Then plan to book the first sitting at dinner on a cruise. The second sitting is often populated with a more gregarious crowd. Then find out how far your room is away from public rooms such as the disco or dining room. Don't forget, rooms close to the engine rooms tend to be noisy as well. Longer cruises are for more than 10 days and are generally more formal.
Shorter trips are more casual.
Certain cruises tend to attract an older, mature crowd so make sure the cruise you're thinking about fits your lifestyle. Larger ships cannot dock right in the port. In these cases, your ship will anchor at sea and ferry you to shore by tender. These small crafts make frequent round trips, so you can get back aboard ship at various times. Just ask a crew member for the schedule.