It's a surprise, in a way, because she's been nursing a baby for so long that there are parts of her that haven't felt at all sexual in seems like forever--but it's not an unwelcome one, at all, and right now it's definitely not the baby she's thinking about. She makes a desperate little sound and nudges him back till he's against the table and she's pressed against him and there's not much inhibition to any of it because she's not thinking. She wants her husband back, she wants all the little intimacies that come from knowing someone that well and at the moment it's almost like she has that again.