What cruise line would be appropriate for a romantic getaway?

mentalsquint asked:

I’m planning a vacation for later this year and I was wondering what cruise line is the best for couples. We are looking for cruiselines that are not so much family oriented, because we are looking to get away from kids for a while. Also something that is relatively inexpensive. I KNOW all cruises are rather pricy, but just give me some ideas of where to start. I’ve never been on a cruise before and I’m clueless as to where to begin my search. Any suggestions?