I think they are perhaps trying to convey unalloyed passion, as you said, but it just comes across as violent, selfish and distasteful - more akin to unrealistic hardcore pornography than actual romance.

I don't think I would be particularly beguiled if my belovèd ripped my shirt off, slammed me into a wall and headbutted me in the face.

I think I'd be rather nonplussed, actually.