Oddly, that re-setting up never applied to men...
Rape always has been a trope in tv, especially on soaps, and I think it's time to end this.
On "Dynasty", with Krystle and Kirby, I think it was quite interesting because the reactions of both women was ambivalent (they both more or less denied it). Krystle's rape in particular was not really used as a plot device.
But on "The Colbys" it was simply unecessary, Fallon should have been willing to have sex with Miles, it would have show that she still kept some feelings towards him, like an unfinished business.
And I have a lot of instances in various shows with unecessary rapes...