The ease of making money in America is absolutely a bad assumption. And all the hard work, which challenges her dignity, is a believable and important outcome of her naïve expectations. Similarly, her belief that getting a green card (especially by marrying someone) would not have challenges and consequences represents a horrible misunderstanding as to how things work. And it’s easy to see that it would provide her with very difficult options that could be extremely costly in terms of money, bad relationships, self-image, and expulsion.
There’s a lot of “gap” to create story here. Good job!
The lessons she learned can deepen the story. Usually a hard-earned lesson is related to more than naïveté (at least in stories). That’s not essential, but it does seem to be part of your story. You mentioned pride and sloth. I’m not quite clear on the pride part — perhaps she thinks she’s smarter that other people in Poland? Or that she so special Americans will embrace her? Or does she believe that she is such a great artist that doors will open for her immediately? Or so charming, everyone will want to help her?
Sloth is easier for me to understand. It’s pretty clear that she did next to no research before she headed off for the US. She knows nothing about immigration rules or the US economy or, more specifically, the market for art. I also wonder if she has deep-seated difficulties with relationships. It sounds like she has bad relations with her family in Poland. Why is that? It feels like there’s something transactional about her relationship with her “best friend” Chris, as well. Looking at how she connects with other people might be mined for powerful story ideas.
On finding empathy. That involves feeling the hurt of someone else. Seeing the world through their eyes. “Veronique is an adult now and should know better and judge what’s she is doing is wrong.” is a statement that can’t lead to empathy. It is a judgment against her with nothing on the other side balancing it. It is a starting point that precludes finding empathy.
As an exercise, it might be interesting to write a scene in Veronique’s life where she falls from grace. Whether she was six or 12 or 24, if you can imagine her last chance of becoming someone you could admire, and then the tragedy of her missing that opportunity. That scene would probably provide the key to empathy. Obviously, it’s not a scene that would be used in the story, but it could be a scene that would open up new possibilities for storytelling (and not just for this novel).