been on 2 with singles cruise groups.
pre-cruise dinner and party/gathering, coctail parties on board, dinner tables are close together but not assigned seating so you can mix and mingle. Games, deck parties, karoake parties, salsa dancing lessons,
Wine tasting (AKA Cabin Crawl party).
Singles cruises also normally have special shore tours set up for their groups for additional charge, nice to stick with your group while you are in ports.