How do we know that Will and Beverly never had some descreet sex before, i won't tell Jean Luc if you wont tell Deanna.. LOLYa, why would Will mind? it's not like he ever turns down anyone for sex. In Conundrum he sleeps with Ro even though he could not remember anything about who she was to him. Hooking up with the chick that used him to get the 'game' on the Enterprise, also the farmers (do you not like girls will..) daughter in season 2, falling in love with a holodeck Minuete, etc..kinda tells you where his limits (or lack there of) are.
Not even going talk about will and his choices in 'The Outcast' LOL
This is precariously close to blaming the victim -- happens frequently in rape cases, where the defense uses the victim's prior history try to prove that it wasn't really rape.
That said, I'm not convinced that what Crusher did should be considered rape. I just watched the episode, and it was Riker/Odan who kept wanting to touch her, who was pretty much seducing her. To me, the problem with her actions was that she was his physician, and a sexual relationship between doctor and patient is unethical, no matter how consensual.
The question that nobody is asking: Did Odon take advantage of William Riker? Shouldn't he have respected Riker's own relationships/friendships and stayed away from romance with Crusher while he was in Riker's body?
a clear yes to the second question but it doesn't matter if Odan in Will's body "seduced" her, because it WASN'T Riker himself doing the seducing. It's like having sex with someone who's unconscious.