Why would she do that? It's absurd

Reginald Shaw:

[walking forward, slowly]
Alexander, is it you? Truly? Frank Taylor:
Truly. Reginald Shaw:
Show me your teeth. [Frank opens his mouth, only showing his teeth] Reginald Shaw:
Aleaxander has crooked teeth, stained from excessive smoking. Frank Taylor:
Braces and electronic cigarettes. Reginald Shaw:
He had a high forehead. Frank Taylor:
I had a migraine for two weeks after the remodel. Reginald Shaw:
You sound different. Frank Taylor:
Voice chip implant. Reginald Shaw:
No, no. I mean the way you speak. Elise:
Yes, that's right. Alexander was English. This man is American. Frank Taylor:
[with a slight British accent]
I've actually gotten so used to the American accent, I find it a tad difficult to go back. Elise:
[scoffingly]
That's pathetic. This man is not Alexander Pierce! He's a tourist. Reginald Shaw:
A tourist? Elise:
Someone I happen to sit next to on a train. Frank Taylor:
[pointedly to Shaw]
How would a tourist know that you kill every man your wife has ever slept with? Elise:
Because I told him that. Reginald Shaw:
[to Elise]
You... told A tourist? Frank Taylor:
Why would she do that? It's absurd