Sookie really needs to figure out how those powers of hers work on 'True Blood' (Sun., 9PM ET on HBO). Just imagine what she could do if she could not only use them at will but know what they were going to do.
In this case, she could have probably cured Eric long ago, though in retrospect that might not be the smartest move. The Eric she fell in love with was the broken Eric. The Eric she stopped from killing Bill was under Marnie's spell, but Sookie's white power blast cured him of every spell Marnie had put on him.
Then Sookie told him about her mixed feelings for both Bill and him, while Eric 3.0 admitted that he loved her and acted a lot more like Eric 2.0 than Eric 1.0, to Pam's shock and dismay. He did, however, suit up and find his inner cold-hearted jerk a little later when Tara's life was on the line as Bill planned his frontal assault on Antonia.