Women in unchangeable (toxic) relationships typically have the same expectations that they would have of changeable (normal) relationships, and so they get caught up waiting and expecting the situation to get back to the "normal" they saw in the beginning. The tactics and actions I mentioned above play a total head game on her, and keep her second guessing herself and always wondering if she was right about the beginning and he changed, or if she had assessed him incorrectly right from the start, and he deceived her.
She cannot decipher which is the real guy~the vulnerable one she met in the beginning, the one who acts normal for the long stretches of time, or the nutty one who is playing head games? Or, she wonders, is it her? In the day to day moments, she questions herself because he acts like she is imagining all the stuff she is experiencing. She starts to wonder if perhaps she IS misunderstanding him. Privately, she thinks, "Could it have been my mistaken memory...did I forget...is he really right and he never did say X, or agree to Y..." but then she remembers he did....and the cycle in her mind continues. Again, it's a total head game and these warped guys are very good at it, and convincing.
If you notice these strategies or a pattern of incomplete follow through, start watching to see if there is a lot of word play going on, or if you feel he is being secretive. Watch to make sure the changes you requested happen, and if so, how long did they last, because improvements don't last long with these guys.
This is crazy-making stuff, and it's not easy to see when you're in it, but if you do, or if you notice it in hindsight, you are already a step ahead of most women, and on your way to breaking free, and finding a peaceful, normal relationship. It is not unusual for the breakup to be very difficult and unending, by the way, so expect a long journey, and if it starts wearing you down, check out my Women-Centered Start Over Programs to get yourself completely free and trusting yourself again quickly.