People who were abused in their families of origin may practice the same abusive behavior towards themselves. They may also pass it on to their children. This creates a sick, and sometimes fatal, cycle of abuse that repeats itself generation after generation.
Therapists talk a lot about boundaries, but we're not always clear what we mean by "boundaries", why they are important to an individual's mental health, or why they are important for healthy relationships.
Men and women have different needs and communicate them in different ways. This can create some serious misunderstandings, hurt feelings, frustration and resentment.