Mother-in-law Hell

My husband and I have been together for 18 years and have four kids - five if you count his mother. She is such a shallow, fake human being. My parents taught me to always respect my elders and do the right thing…well, I don’t know how much longer I can be respectful. I gained a lot of weight since I started having children and she’s always made sure not to let me forget it. Each time I was pregnant, she would come into town and she would say that I’m getting too fat and that I use to be so beautiful. Unfortunately, she would always stay with us after each child was born to supposedly help, but really to make me feel bad and point out what I was doing wrong and would not give me any privacy with my children. Well, now she and my FIL moved to the states permanently. They live 5 minutes away from us and I’m going insane! They both show up at my house unannounced whenever they feel like it (when my husband is not home). I live in a ground level ranch home with no basement, so believe me, there’s no where to hide. They come in, sit at the kitchen table and just say and do nothing. I offer them drinks/food and they always decline, so I try to continue my routine with them looking on, but it’s very awkward. When my kids ask me for things and she’s around, I go to get it, then she rudely pushes me out of the way and gets it herself. She always tells me to cut my hair and dye it, she stares at my stomach as if it were a monster (although she’ll get mad if I don’t finish the big plate of food she serves). She likes to insult me in any which way she can, but when my/his relatives are around she calls me these sweet nicknames that make my skin crawl cause I know she doesn’t mean it.
She buys me blouses and jewelry she would wear (I’m 34 she’s 63). Last Christmas, she bought me a long blouse/sweater with pearls sewn on the neckline….I looked at it with horror. Then for new years eve, she wore the same exact blouse in a different color! Now, I think she does this on purpose cause she buys her petite 37 year old daughter jewelry and clothing that is nice. One last thing I’ll mention to show what type of person she is - Last year my 6 year old had to have sensitive back surgery and would have to be laid out flat for 7-10 days. My husband and I thought it’d be best for me and my son to stay with my mom so his brothers wouldn’t hurt him. My MIL offered to stay at my home with the kids and a small dog (I was dog sitting for a brother in the military). After staying at the hospital for 3 nights then on to my moms home she called me there and started complaining that the dog was pooping in the living room because my house was a pig sty. I just started crying cause I didn’t know what to say - then hung up (she gets a thrill kicking me when I’m down). When my husband got to our home she told him that I was not a good mom, wife or housekeeper (granted I made sure the house was in order before leaving). Fortunately, my husband knows what kind of person she is, and yelled at her for being so rude and making me upset. It’s a year later now, and she hasn’t changed a bit. I could go on and on with the horror stories, but it would be a novel by then.