its the estrogens , you have to have empathy, show her that she means alot to you, while shes crying, put the 19inch cannon arm around her shoulder,the other arm towards the titts and then say something romantic,like"baby,i always wanted you to ask this"
she will say ,washing the tears from face"yes,what?"
then ask her if shes up for bit sex when shes done crying.
they have feelings, respect them.