I don't know, but I think even if they had consensual intercourse, she can claim assault. There have been cases of spouses doing the same, when it wasn't forced. Maybe not in CO., but I am certain it's happened. Please see my previous post on Class 3 Felony Sexual Assault. You will see that he either used force, threatened the use of force or drugged her.
I see your post, what is the source (got a link)? Thanks.