I don't think Nicole went to the farmhouse, intending to declare her love for Eric or have sex. As someone noted, when she learned from Chloe what Brady had done/said to Eric, and realized the sacrifice Eric had made, that was huge, and she did not want him giving up his life for her. THAT is what she went there for, not even thinking.
As it turned out, events progressed from there. Eric loved her that much, he would give up the life he loved (for the second time!!!) whereas Brady, who already had her and their family together, could not keep himself from attempting to manipulate her.
Yep, Eric & Nicole cemented their love, & Nicole regrets that she had not talked to brady first, and has to now, after the fact. But she is not going to hide it, intends on telling him. Brady is the loose cannon, and has brought the destruction of the life he had with Nicole upon himself.