Is the curse of the angels limited to the woman who refuses her husband's bed, or does it also include the man who mistreats his wife or expels her from her home and possessions? And can Allah fulfill the desire to meet fictional (non-human) characters in Paradise?

Islam is a religion of justice and mercy, and a Muslim must submit to its rulings, because Allah knows His creation best. There are authentic hadiths that forbid a woman from harming her husband and warn against her refusing his bed. As for the actions of the men mentioned in the question, they indicate bad character and contradict the good marital companionship enjoined by Islamic law. A husband must treat his wife with kindness or separate from her with grace. The angels questioning men's actions is a matter of the unseen which cannot be established except by an Islamic proof. As for the questioner's attachment to "the young men who are in the state you described," she is advised to seek psychological treatment, for Paradise is entered by Muslims who obeyed Allah and avoided His prohibitions. It is advised to stay away from such thoughts.