The fictional part rings true, especially the desire to take your ex to a hiding place. I get that.
When my first husband was in treatment I used to give myself a break from sitting in the room with him. I'd go on the roof and look out over the big cancer complex. On the next roof over, patients in clinical trials were taking a similar break, in their wheelchairs, catching their own fresh air and having a smoke.
There was a little cloud hanging over them, like a caul.
I'd watch them, waiting for an explosion from someone's oxygen tank. Like watching a NASCAR race and looking for a crash.
If you haven't already read this, I think you might "enjoy" it.