What is the ruling on demanding that a sister who supports the household pay for household expenses, and is the questioner sinful for what has happened?

It does not appear that there is anything that calls for disliking your sister or that you have committed a sin. There should be agreement and satisfaction between you regarding the spending [of money] to preserve love and harmony, for believers are brothers, and kinship ties are connected. It is advised to pray for the improvement of the situation and to establish sound foundations for understanding, and to seek help from trusted individuals when needed. Marriage and each of you moving in with her husband might help resolve the problem from its roots.