My relationship with my husband and sister is very stiff, and so is my husband and sister. What should I do in this situation?

This stalemate will do harm to both of you and lead to more and more contradictions. If you want to live a good life and a harmonious family life, you must handle the present situation well. Since you don't want to bow your head, why don't you put a low profile and get on well with your sister-in-law? If you get along well with your sister-in-law, and your husband is embarrassed to say your sister, he still cares about this. Communicate calmly with your husband and tell him about your relationship. I think he will understand your pains. I will thank you and wish you happiness!