Forgiveness and acceptance go together, because forgiveness, as I understand it now, is about recognizing that we truly were doing all we were capable of doing. With accountability, there is an expectation that you or I can do better. To that end, in accountability I demonstrate respect by communicating boundaries, clarifying expectations, and working to build mutual understanding.
With forgiveness, it is clear this was the best we could do together, and expecting more from the relationship gives rise to greater hurt. To forgive is not to say that what happened was acceptable, or even that the relationship can or should be restored to what it was.