Friend at work is getting fired, and I’m replacing her

My friend/colleague at work is being fired this week, and I’ve been asked to serve in her position on an interim basis.

I know logically that my actions don’t create her thoughts and feelings, but I’m indulging in confusion over how best to handle this situation and how I want to show up with her after finding out.

I’ve decided not to give her a heads up about the termination as I worry she may undermine the company if she knows ahead of time, and I stand by that decision. But I am still dreading her reaction when she realizes I must have known earlier and am now taking her job.

I know those are thoughts. I want to talk to her after it happens if she’s open to it, but I’m not sure what to say.
I don’t really want to say anything; I want to acknowledge what’s happening and then listen. Then I want it to be over… Any guidance or suggestions of thoughts to go into that conversation with?

Thank you!