Okay, I'll do my amateur psychologist bit on Stephanie
Actually, I came across many Stephanies when I lived/worked in NYC (although most of them were named Gina, not Stephanie). My take is that she was a secretary at a Manhattan public relations shop or maybe a show business agent's office or movie production company. So, she would have had the opportunity to meet Al Pachino and other famous people, but it's not like she was hanging out with them or anything. More like she'd have been asking them what they wanted in their coffee. But, still, that's meeting someone!
I don't think she was a stupid girl; she probably picked up enough knowledge about several subjects to sound like she knew what she was talking about to someone she considered inferior to her (ie Tony and his friends), but I bet a lot of what she said she was just parroting from her boss/sugar daddy/older guy friend. Remember how she referred to something as "neat" and he lit into her, saying that "nobody says 'neat' anymore"?
I felt like she would like the opportunity to go to school, but probably never will.
I don't like her either, but not because I think she's living a lie (not a lie; more like an exaggeration). I definitely think she was using poor, dumb Tony as a sounding board so she could talk about things that made her feel better about herself. Of course, I didn't really like anyone in that movie except for poor Annette (who now plays the mom on a Disney Channel show. If her Disney children only KNEW

). And also, I had one of those fluffy jackets just like hers! lol
Please pardon all the tense jumping in my reply!
What is your take on the character, aabby? Your family sounds fun, BTW