facebook is definitely listening. We have had many instances where wife and I discussed something and an ad appeared on fb related to that.
The very next day I was visiting Phys.org like I usually do and an ad appeared about dock supplies and repair. I don't even have Facebook and never have! He does and is kind of active on Facebook. Both of our phones were with us at the time of the conversation and I was connected to his WiFi network at the time. I'm on Android and he's on Apple user. Out of all the ads they could have pushed to me... dock repair!? I wish I still had that screenshot I sent him. It creeped us both out.