After Bakemonogatari, Hitagi enlists the help of Hanekawa to try to be "normal" again. That is, she wanted to be able to interact with people without being abrasive and violent. It must have been pretty damned hard for her to hold herself back because when she held Koyomi captive, she really tormented him.
Since Hanekawa was helping her, Hitagi had to follow her orders so she was like her master
. Well, despite all this help from Hanekawa, she wasn't able to make any progress.
It wasn't until she confronted the first of the five conmen that defrauded her family that she was able heal. Just so that you know, Kaiki was pretty scary
. He was in the same occult club that Oshino was in when they were in college, but despite being able manipulate Kaii, he doesn't actually believe in them. He did more than just defraud Hitagi's family though, he also pushed for her parents to get divorced so Hitagi sees him as the one who stole her happiness even though she realizes that her parents would probably have gotten divorced eventually anyway. Kaiki is incredibly manipulative and can read people's insecurities very easily. It took a huge amount of courage for Hitagi to be able to confront him. Hitagi told Koyomi that she wanted to confront Kaiki so that she could stop being shackled by her past and move forward. After she confronts Kaiki, she is able to be open with with people, even more so than when she was in junior high according to both Kanbaru and Hanekawa. She had kept the same hairstyle since grade school because her mom had told her that it suited her, but it was just something else that was binding her to her past so she changed it. She says that if someone who has been disappointed in love can get their hair cut, then someone who has found love can have it cut as well.