Given the great number of comments and discussions going on here, I just wanted to throw my hat in the ring.
My SO and I are big on lit. Well, hell, actually we specifically champion more alternative forms of lit while enjoying traditional lit (books canon or not)... That is to say our theses and major papers involved studying rap, graphic novels, film, and video games. So with that in mind, you mention your SO is less into film, but does she understand the mechanics of film and how they translate into traditional literature? If she can understand that the opening of The Graduate isolates and weakens the protagonist just by his position in the frame, then your task is much easier.
You see in studying literature, the biggest issue with some people tends to be how storytelling functions. Everyone knows that we have the same stories: the factors change but the formulas are the same. There is more than one formula, but you can strip everything down to the basics, and you should when studying a story. I know early on when I first joined Reddit I said I enjoyed how Hotline Miami captured the mix of arthouse and gratuitous violence through it's pacing and dialogue like the film that inspired it (Drive), and the top comment against me was some guy saying "psh, you could write that story on a napkin" or something along those lines. So what most people tend to think is that if you introduce lots of characters and put in lots of words and details, you have a great story. That isn't true. More details can make a good story, but having less details doesn't make a story bad. So, a good practice for how storytelling works and how to critique it, is actually to write the story as short as possible, on a napkin if you will. You will see that a lot of stuff gets reused and as soon as you see what is reused, then you can examine what makes a particular story special or unique. So with that in mind, you probably shouldn't try to compare a video game's narrative to a book , that just spells trouble. The second you say Bioshock is like Atlas Shrugged or Spec Ops the Line is like Heart of Darkness, you have now set up the expectation for lots of words and mechanics that these video games don't have and don't have to rely on.
What you should instead focus on is how themes and mechanics are translated into video games and some unique aspects of video games that other mediums don't have. Life is Strange most easily deals with acceptance and the futility of choice, this translates into the time rewinding mechanic that doesn't really happen too much in books: you can choose to skip over one paragraph in a book but the story is linear and you might miss something, in LiS you are essentially choosing to read one paragraph over another that might affect future paragraphs. It is not the only game to have a choice mechanic, but writing in the time rewind essentially replaces save/load mechanic of other similar games, and makes it organic.
Spec-Ops the Line is predictable and pales in comparison to its inspiration in a number of ways, however it is great at dealing with smaller details. The slight hints of warped reality are a great way of showcasing the unreliable narrator in video games. Call of Juarez Gunslinger is another, more direct taste of unreliable narrator in video games with a strong Old West setting to boot. Bastion and Transistor are great examples of collaborative storytelling: falling off a platform X amount of times or picking arbitrary choice over another earns the player some narration.
I am surprised this wasn't mentioned more, but Kentucky Route Zero definitely handles collaborative storytelling and choice well.. Do you know how tough it is crafting magical realism in books? It's even tougher in video games, and the player is helping to craft their own story with the game. It's dense for film fans as well.
The Swapper is another one that I expected to see more. It is a bit heavy handed (the space ship is called Theseus...), but I know my philosophy and lit professors all enjoyed its clever mechanics, atmosphere, and artstyle. The artstyle is imaginative and strictly visual while the gameplay is just platforming and puzzles done well. There is no grand theme or narrative device to show off here, instead you are just showcasing what video games can look and play like while indirect narrative hides in the game.
Dark Souls! Just kidding, but not really. Indirect narrative is strong here too, and I liken it to cinematography in some regards. It also shows off consequences in gaming very well. That said, it can be tough for her (I know I introduced some of my non-gaming friends to it and half beat it easily while the other half were stuck).
Sherlock Holmes Crimes and Punishments was a great detective game but I am hesitant to have you show her that because nothing really holds up to it's synapse matching accusation mechanic (though spots of LA noir come close). Again though, this a great highlight of how choice mechanics and video games can work.
The Stanley Parable and Dr. Langeskov can be funny experiences to show her after she has had a foundation (whether through playing or watching) some video games. It's more a revisionist take on what games are or can be, and it's pretty funny.
I would offer more but there are so many great things here. If she is into analysis or theory, there are just a wealth of things out there. If she takes games at a surface, it's as big of a mistake as taking books on surface level: you might enjoy it, but you are not going to be moved as much or by as many.
Anyway, if you ever get around to reading this, I would be happy to talk about video games, rap, or graphic novels as literature, or even books as literature since you mentioned her wanting you to read more.