The story makes it seem that David raped Bathsheba. I doubt that she had the option of refusing his summons, or may have feared for her life if she turned down the king. And she couldn't have been a willing participant, or god would have rendered judgment upon her for adultery. Either god conveniently let her slide on that (an action that directly led to her husband's murder), or she was innocent of any wrongdoing.
It's a chilling story, when you consider that the people who paid with their lives were the innocent husband and the innocent infant, who was stricken with a deadly malady in order to punish David (who, unlike his unfortunate child, had the opportunity to repent and avoid a death sentence). Plus, his pairing with Bathsheba leads to the birth of Solomon, a great king who also loses his way (but not before becoming part of the lineage that leads to the birth of Jesus... at least in Matthew's gospel).