'By introduces the new vvariables that he has added. In the act of mentioning them, he introduced them- once stated, presumably, they had to be taken into consideration.
In the second, the woman was shamed and pressurisaed into going back to the first person who had humiliated here. I would imagine that this was done by people trying to encourage her to stand uup for herself, but context would indicate the exact reason.
Student or Learner