Chapter 1
Gretchen will spend the entirety of Chapter 1 working on the cable cars. Exhaust all conversation options with her to unlock this trophy.
Some people have reported trouble getting this one, and I'm not sure why. I've cut and pasted directly from my walkthrough here if you want step-by-step instructions for this one:
So, how long have you been here?
How did you get here?
Now that you mention it...
Please, go on!
Talk to her again
About the cable car...
And you really want to go up there?
What was it you do for a living again?
What kind of a cult is it you're looking for?
This cult...were they dangerous?
We might as well have a coffee before we leave.
If the trophy doesn't unlock, talk to her about the burglary in your room and it should.
For this and all other conversation trophies, you need to actually choose the “Goodbye” (or whatever) option; any conversation option that just ends the conversation automatically will not cause this trophy to unlock. None of these are glitched, so if it doesn't unlock, keep checking dialogue trees you've already used to see if there are new options to choose.