Under these circumstances, it is advisable to engage both parties in individual therapy, not with the same therapist. Both parties need help, guidance, support, and facilitation in education and self examination. Without this, there is little hope of things in the relationship getting better. It may even be advisable for the couple to separate for a time. Of course, this idea may be vehemently resisted by one or both parties, for a variety of reasons.
When there has been violence in a relationship over an extended period of time, the psychological and emotional dynamics between the parties are deeply dysfunctional, self destructive, controlling, confused, and, of course, dangerous. The unfortunate reality is that these relationships not infrequently end in death for one or another, or sometimes for both people. Over time, the violence tends to clearly escalate without meaningful intervention. It simply is not the case that things will "get better" on their own.
If you know people for whom this situation exists, or if this is true in your relationship, please find a way to look for and ask for the help you, or they, need.
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