Like most films by Woody Allen, this too comes across as a film adapted from a play, specifically Tennesee Williams's 'A Streetcar Named Desire', but it isn't.
Blanchett's character is larger than life. A socialite widow of a crooked investor who conned lots of people out of lots of money, including Jasmine's very own working class sister Ginger. It is Ginger who Jasmine turns to for help when she is left homeless and penniless. Or not so much 'turns to' as imposes upon by moving in to her modest apartment. Sharing a small apartment with Ginger and her two sons is not quite the style of living to which Jasmine is accustomed and she shows no restraint at letting Ginger know this.
Jasmine is supposedly broke though as Ginger cleverly points out, she seemed to manage to fly first class to San Francisco to stay with her. How? "I don't know Ginger! For God's sake! But I can not fly coach!" Jasmine is an odd self absorbed creature, surely on the aspergers scale somewhere. She has no empathy, no ability to understand other people's feelings, no understanding of what to say and what not to say. She is stuck up and arrogant. So understandably she is a little hard to watch. Though Blanchett being Blanchett, she manages to make this pompous creature watchable, though even she can't make us feel sorry for Jasmine.
This film may not be for everyone, at times it is irritating. But if you are a fan of a fantastic performance and a strong layered character you'll enjoy it. Obviously the academy enjoyed it! She did win an oscar!