Probably cuz they got hurt one too many times before or saw close ones getting hurt so they’ve learned to build walls around them to protect themselves making it hard to show much affection. Generally Cancerians are very caring and love to show affection but they like to guard their strong sensitivity under this tough exterior.
Of course!! They’re very caring and protective of their friends and family. However, if you’re an enemy of a Cancer or outside their circle of friends and family, they can come off a bit mean, it’s just them being defensive though, especially since they like to build walls around them to protect themselves. Cancers are also highly manipulative since they have great intuition, but it depends whether they use this for good or bad.