I do. I'm not sure how I do with them, actually. I don't think it is my forte, that's for sure. But then relationships, romantic or otherwise, are part of characterization, and I'm not up to par with that aspect of the craft.
I guess you could say I'm willing to go all the way because I have done. But not between the romantically-involved. There has to be a reason for me to show a love/sex scene. I don't have a problem with doing it, but I doubt I will ever take the details too far. I don't have a story line/character arc that demands that in any of my present WIPs.