I find this interesting - why do you find the claim that it is difficult or impossible to describe something we have no experience of to be romanticised or sentimental? I think that is largely true for me - there are many things I haven't experienced, and I have no way of describing them. I mean, I can read about what it feels like to be a parent, or what it is like to drive a car, or snorkle, or receive the Nobel Prize, but since I have no personal experience of it I have no way to describe it myself.

Then again, good authors can write believable accounts of things they have never experienced. But I still don't see the connection to sentimentality or romance.

And also, just because I have experienced the same thing as somebody else, it doesn't follow that our experience is the same. (That's why I don't believe in "female points of view", for instance.) I have experienced love but I'm pretty sure that my experience is not the same as anybody else's, and I don't think I could describe it either.