How might a late-diagnosed autistic partner (F40) process causing serious harm?

TL;DR: My partner of a year (I'm neurotypical, she's late-diagnosed autistic) broke serious trust with me. When I ended it, she showed no real grief, apology, or ownership. Instead she offered a Venice trip and then HR-speak about "different assumptions." Trying to understand how she might actually be processing her responsibility, even if it doesn't look the way I'd expect.

Six weeks ago, I (M40) went through a painful breakup with my partner (F40) of one year. I am neurotypical; she is late-diagnosed autistic. We agreed this was a pretty rare relationship and treasured it. We were good to (and for) each other. There were no signs of distancing or major difficulties.

What occurred was by any standard a violation of trust, dignity, loyalty. But the communication has been unusual and I could really use some help.

When she told me about it, her focus seemed to be totally on her experience, with no modeling of my possible reactions. She was genuinely shocked when I got up calmly, got dressed, and walked to the door.

When I told her the relationship was over, she cried and moaned "Why?" The next day she texted and offered to take me to Venice. I said thank you and declined. The day after that she texted and called incessantly.

There was no recognition. I said very little, but over the course of a week her messages centered around, "I think we stumbled into realizing we have different assumptions." Everything she said sounded like it came from Human Resources. I realized we were at a point of no return and said again that it was over.

Since then: no grief, no longing, no regret, no apology. Just silence. I'm not sure I can explain how disorienting this has been.

I'm not looking to be angry or resentful about it. I'd rather understand. How might a late-diagnosed autistic woman process something like this? What might her sense of responsibility actually look like, even if it doesn't show up the way I'd expect?