How do I not get angry or mentally drained?

My mother is 77 and constantly repeats the same terrible childhood stories to me and anyone that has ears! She complains about my husband but praises him in his face. She tells lies about him to my family. She constantly criticize how I handle my husband and grandson that lives with us, my hobbies...crafting and photography, and even how I handle my dog!! Tells me what I should do in situations in my life and what I should say. She tells me lies about what my husband has done or things my grandson does....his behavior. She criticizes me on how I keep my house, says I keep too many things. She lives in what is actually a pool shower room that she's turned into her living space. It's tiny and has a parrot I got for her to keep her company. She babysits my 1 1/2 yr old black lab. She tells my She has no manners and I am wrong for letting her on my furniture. Critiques the way I will tell my dog no or to get down. I'm 54and have been in therapy since my 20's because of her. If I'm happy she will act depressed and if I'm down about about something she seems chipper and happier. I've lost weight and tells me I look terrible from the shoulders up...I'm too skinny and my eyes or sunk in. I can be around her for 5 minutes and I feel exhausted and have a pounding headache. She talks LOUD and non-stop! She rarely lets anyone speak and if she does she tell a story that she had the same thing happen to her. She acts like she has the answer to the worls problems, and like she's big and bad. She doesn't like to be around anyone she doesn't know. On holidays when my step daughter comes over with her boyfriend my mom will give some excuse why she has to go back to her place because of a headache or sick. She doesn't like to drive so she stays in her place all day. Her hygiene has really declined! There's only enough room for a twin bed where my mom lives..she has no other furniture like a chair or recliner. She watches TV all day and will nap and be up in the middle of the night. She only has a microwave and coffee maker so her diet is poor. She won't come in the house when my husband or grandson are home and if she does it's in the kitchen for a few minutes. The weather is getting hot but won't turn her AC on because it's expensive to run. She says she takes a shower about every 2 weeks because she says she doesn't do anything to get dirty. She has really long hair and washes it even less. I walk into her place and it's stuffy and stinks. It's embarrassing when my step daughter comes over and right off the bat she'll talk to her but she will tell some terrible thing about her childhood. So my step daughter tries to avoid her. My grandson is biracial and talks about him growing up to be a thug. I've caught her making mean faces at him when she thinks I'm not looking but will talk about him making terrible faces at her. My gson almost gets hysterical if he thinks she's going to babysit him! My husband is a champ dealing with her, even after he's heard her on the phone with someone telling lies about him. I try to.change the subject when she starts telling me untruth or stories but rarely helps. I've been around her and don't get to say much because I know she'll have something negative about it. She is always talking and acting rude. She says she's 77 and can say whatever she wants because she's 77. I'm just tired of dealing with her. My brother can handle her from a distance but would never want her to live on his property. She'll have to call the bank or some business over something and before she calls she goes into this story about what she's going to tell them if they say this or that. It's like she's telling me about something happens or how it's going to turn out before she calls. I'm tired of all this! Physically, mentally and emotionally. She will say someone needs to go to counseling but doesn't think she needs to because she went into a psych hospital over 40 yrs ago and watches Dr Phil. Any suggestions? Please!