Why hadn't he changed the locks on the house?
So his GF, who seems to have known him for quite a while, doesn't know what his estranged wife looks like? That has to be the least-curious serious GF on the planet.
I'm roughly at 17:00 or so. It's not like he'd have even noticed the cost of having them changed. It's standard procedure after someone with the keys to the locks moves out and you don't want them coming back in when you're not there. Also, why no alarm system in a house like that one?
I'm sure there will be a lot more WTF things to take potshots at, but that's all so far.
“There comes a point when seduction is over and force is actually being requested.”