My gf got mad at me for using AI

My gf (22F) is mad at me (24M) for using AI to help me rephrase a section of a PowerPoint presentation for school. This class has been really tough and because of the grading standards for the program I am in, a 77% is a failing grade. I have a 91% right now, which seems good but this project is worth 25% of my grade and I just can't afford to mess it up at all.

She caught me using ChatGPT to rephrase the things I had already written in a more concise manner. This is the only time I have ever used AI to do homework. I figured it would be okay to use it this one time since the ideas presented in the slide were my own and all it did was cut out some unnecessary and inefficiently worded parts. I just really want to do well on this assignment because failing the class would mean setting back my graduation at least half a year, which I literally cannot financially afford.

She claimed that I was making myself dumber by using it and that I wasn't really using my own brain and just letting the computer do it. I explained to her the situation but she wouldn't budge on it. I know she's anti-AI as she is an artist, which I respect and I do not support AI art, nor do I support AI music because I myself play guitar and some other instruments. I really don't support AI at all, I just used it this one time out of paranoia of failing this class. Am I an asshole for this?

I recognize that I could have totally just asked her to help me but when your presentation is on neuroanatomy, its hard for an outsider to just hop into it and have meaningful suggestions on how to phrase words they don't even know (think dendrite, ganglion etc.).

She claims that she did her degree without AI at all. Which is valid and true, however her degree was in studio arts with an emphases on oil painting. I'm not saying that degree is worthless or invalid or anything negative, but mine is medicine, which is generally more difficult, and I don't think anybody would genuinely disagree with that. All I'm saying is that between the rigorous grading system and the level of knowledge that must be attained, I think this was a justified use of AI.

She currently will not speak to me and is sulking in our bedroom. What do I even do beyond apologize?