Some do. In your case though your XW has some SERIOUS mental health issues so she's not exactly in a typical state of mind.
Sure most get selfish, but they don't go to the extent as yours did and get married to a guy they just met in a week while popping pills and asking for money from you.
You can't place your W in the typical WAS role. Prolonged use of the drugs probably increased her paranoia and addictive nature. The only thing that can solve that is professional therapy or something so life altering that she'll snap out of her drug-fueled thinking.
M-43 W-40 2D - 9 and 5
Emotion, yet peace. Ignorance, yet knowledge. Passion, yet serenity. Chaos, yet harmony. Death, yet a new life.