Mother-in-law Hell

I truly have the MIL from HELL. DH and I have been together for 7 1/2 years and married for 5. We have two boys-one is 4 1/2 and the other is 15 months old. DH has two older sisters and a younger brother. My MIL has always been very opinionated, manipulative, selfish-the type who sees her DILs as “competition”-in other words, she cannot handle any other woman being a part of her sons’ lives. (My BIL’s wife deals with a lot of the same stuff I do.) MIL has a lot of health problems. She is about 5 feet tall, and weighs about 400 pounds, and is confined to a hospital bed in the middle of her living room. She has emphysema, her knees are shot, her kidneys are barely functioning, she can’t sit up, let alone stand up or walk, and she pretty much just runs the show from her bed. She needs to go to a nursing home, but she refuses so instead, my poor FIL does EVERYTHING for her, from cooking her meals to diapering her, etc. Anyway, the house is full of medical equipment, prescription bottles, etc. Their other grandchildren are all grown, so nothing in the house is even CLOSE to being babyproofed-no cabinet locks, no outlet covers, NOTHING. Recently our older son was diagnosed as being on the Autism Spectrum. We explained to my MIL and my FIL that we were concerned for his safety in their home-i.e. in the past he had gotten into knives, we’ve grabbed pill bottles out of his hand, he put Ben-Gay in his mouth, sprayed Windex, etc. He doesn’t understand fear, so the stairs in their raised-ranch house are an added concern. They have done NOTHING. So when we would go to their house, my DH and I were constantly jumping up to grab our sons away from dangerous situations. (Not to mention MIL swears and curses worse than a sailor, uses bigoted terms, etc. in front of the kids when we have asked her to tone it down.) On holidays we can’t even eat or talk to anyone because we spend the whole time protecting the boys. MIL gets disgusted with us and tells us that we are “too nervous” to “let the kids be, they’re fine” and she mocks us and laughs at us! We have both tried over and over to explain to her that our son has autism, he is NOT like other kids, we HAVE to be concerned for his safety-and she will either tell us again we are overreacting and that “she heard on TV the other day about autism” so she “knows all about it” blah blah blah-when in reality she knows NOTHING about our son’s diagnosis. We’ve tried to educate her, but she hears what she wants to hear, tells US we’re wrong, etc. Over the last few months, after our younger son was able to crawl and then walk we stopped going over there altogether-it was a disaster for us with chasing both kids and inevitably DH and I were going home and fighting CONSTANTLY. Due to her health situation, she can’t come to our house, and since she is such a domineering person, my FIL stays away too, or she gives him HELL. I feel like my kids are being cheated out of their grandparents, but I have to make their safety my priority. But as a result, the rest of the family (with the exception of my BIL and his wife, who have our backs 100%) has stopped talking to us-in their eyes, WE are the “bad guys.” It is such a mess and I don’t know what to do. I feel like she doesn’t accept my son’s diagnosis, thinks we are stupid parents, and it’s really affecting me.