why do you think Miss havisham makes Estella play cards with Pip?

Miss Havisham's motivations represent a cruel and twisted revenge after she was jilted on her wedding day. She herself refers to her torture of Pip as one of her 'sick fancies'. Miss Havisham uses her adopted charge, Estella, to make Pip, the young blacksmith's boy, feel inadequate in terms of social position, intellect and love. She tells Estella directly -

..."You can break his heart."

Estella is incapable of any positive emotions and she gloats along with Miss Havisham at Pip's wavering spirit.