Why is my husband's sister always like this? What should I do?

So is my husband's sister. Although pregnant, my husband is not at home on a business trip. She wants my husband to sleep with her at night. They are all adults. God, what if we sleep together and we are brother and sister? No matter how good our relationship is. What do adults think of sleeping together? I really can't stand it because of this. My husband didn't listen to me and called me dirty. Once I went to my friend's house and called him to pick me up in the morning. As a result, he didn't answer the phone and hung up every time. He also sent me a message saying that my sister was sleeping. I was so angry that I wanted to vomit blood, and my nose was sore and I cried. I sent him a message to pick me up. Then he finally picked me up and started talking about him. As soon as his sister heard that her mobile phone was taken away by her, she said that I don't know what I was thinking. She said that she was in poor health since she was a child and could not catch a cold. Their parents don't care, such a big child, he still hates me for this and says I am wrong. I'm really in distress situation. Nobody cares about me when I hit the child. I went home alone and the three of them went to eat hot pot. When they came back to see me, no one asked me if I had eaten. Her sister asked him to get me some brown sugar water to drink. The next day, they all left, so I went out to buy something to eat. Then the gas at home broke down, so I washed clothes with cold water. There is really no way to take a taxi to my friend's dormitory, where my friend works and sleeps. I slept with a friend, and they brought me food when they came back from work during the day. At that time, he said he broke up with me, and I hated it, so I vowed not to leave, so that he could taste my pain before leaving. I begged him not to break up with me, saying that I loved him and would be good to him, and I would say whatever I said in the future. However, more than half a year has passed and life has been good. A few days ago, her sister caught a cold and came to live here with a few months old child, because her husband is a coach and takes students to the exam. As soon as she came, she kept calling and texting at four or five every day to let us go back for dinner. Actually, she wants me to go back to cooking. She said my brother was hungry and poor. It turned out that their father had been angry for months without knowing why. We called him to eat, and he said he did. Every day when we go back, he doesn't come out After a long time, it will be embarrassing for me to go back to see him alone, especially when I start calling him, and he just stares at the TV and ignores me. I am also a thin-skinned person. Can I not be embarrassed often? Then I don't want to go back to cooking alone. Actually, I cooked every day at first. I didn't starve my husband later. Even if I didn't want to eat, I made him something to eat. Every time I eat, I cook it and send it to my husband's mouth. When he plays games, I make him fruits and melon seeds and send them to his mouth. My husband didn't lose weight or get sick. I don't know how she can be a sister. Even after chatting for a few days, we were annoyed that she didn't want to go back for dinner. I bought a duck to stew at home yesterday. As a result, she sent a message to my husband saying that his eyesight was getting worse and worse. She also called her relatives and friends everywhere to complain, and then her relatives and friends called me to tell me about my husband. She tortured her husband at home and tortured us when she came over. She often quarrels and divorces with her husband at home, and then calls everywhere to say that her husband is not good. Once the four of us went to dinner together, and she suddenly became unhappy in the car for some reason. She grabbed the steering wheel in her husband's hand and the cigarette in her husband's mouth to burn him. Oh, my God, she's driving. I have been comparing my husband's ex-girlfriend with me, saying that those women are still rushing to drink her cooking, and she is still dating a woman. I mean, yeah, she's fighting to cook with you. She is very sweet, but is she really good to her husband? Why else did we break up? My husband likes me more now and knows that my sister is helping me.