What mental illness does this sound like

This story is from a few years ago This story I about someone I knew I’ll call her Helen, Helen is Dianas cousin and Helen and Diana were close when they were younger Helen lived with her they were like sisters well Helen and her grew apart they both just went on in life but Diana has always helped Helen anytime she needed it now both of their children are close. Helen had substance abuse issues and Diana would always help her like babysit the kids whatever didn’t really ask for anything in return Diana kind of ended up raising the kids for a while on and off now years go by Helen needs a place to stay and she asks Diana just for like a week well it wasn’t only a week it was like a year Diana was blind to see all the stuff Helen did Helen was very manipulative like she tried to break up Diana and her husband up Helen wasn’t married and Helen didn’t have custody of her kids it was only Helen and throughout this year or so of living with Diana a lot happened Helen scammed Diana of 300 dollars, tried to break up Diana and her husband, got Diana’s teenage children addicted to weed, supplied alcohol and weed to Diana’s children, would always like try to one up Diana like got super close to Diana’s best friend then got drama started between them would talk bad about Diana to others then lie and say Diana said stuff about them ultimately causing spot of drama she also loved drama and anything to ruin Diana’s kids so her kids seem better extremely snakey and also got a lot of drama started between Diana and 4 people bcus of lying and did all this behind Diana’s back very manipulative she would flip the narrative alot to make her self seem like the poor helpless victim also would constantly bring up anything she did to contribute to the household like when she would put money in the house she was staying at she would act as if she didn’t have to help out at all mind you Helen is a middle aged women Traits I would use to describe Helen Snake Manipulative Fake

Please let me know I’m sorry for the grammar