Though there are allusions to the rapes in Finch's novel, they are never (as far as I can discover) explicitly revealed.
The lack of direct discussion about this sensitive subject is probably a deliberate part of the culture of cover up and the silence that continues to surround victims of sex crimes.
More directly, one could consider Astrid's relationships with a succession of men (Paul, Sergio, Ray, etc.) as forms of date-rape, perhaps, as all of the men use her for their own gratification. Astrid's obession with them, in my opinion, does not lesson their culpability as she is vulnerable and the men often take advantage of this fact.