Many victims experience frustration because they felt helpless or powerless when the abuse took place and feel even more helpless and powerless after. In situation of threat, such as abuse, the brain goes into a state of "fight or flight" that affects the way we respond to certain circumstances. It is normal to wonder about “what if” - specially about not being able to see the abuse coming or prevent it. For example you might wonder, "what if" he or she had said no, or said no more times? "what if" he or she had not accepted that chocolate? "what if" he/she had not gone on that outing? 

What can frustration be managed? Anyone can start remembering this:
It was not the victim's fault.
The victim did not deserve it.
There is not a correct way to handle abuse.
There is help available.

If you'd like to read more about this here there is more information: https://www.loveisrespect.org/content/dealing-with-shame-after-abuse/

Patience is the ability to be calm in the face of disappointment, adversity or distress. 

With practice, victims can get better at responding to adversity, and the many frustrations of  life and living it after a traumatic experience.

It also helps to develop understanding and compassion because the victim takes the time to process the situations he/she had to go through. Abuse is never the victim's fault, and it can take time to acknowledge it completely.

To interrupt the cycle of the "fight or flight mode" is important to be aware of whatever one is either saying to oneself, an image, a feeling in the body that is triggering the response that he/she is under threat. 

There isn't a "right period of time" to overcome a harmful experience, being patience with oneself is a ongoing skill to practice.