I really think she is just trying to bait you into a fight. Because it has been so long since you fought about it she doesn't know what to do with herself. I think some where in that mind of hers she is trying to hurt you in some way. Because if you are fighting about this thing she holds all the power. But with you not giving her that power is starting to make her wonder what is going on with you. I don't think she knows any other way to go about talking to you about sex so she just throws these little mean coments your way.
