I've given a lot of thought as to whether or not to post this response, I intend it to be helpful to others plan cruising with "unknown" roommates.
It is very important to know what is important to you in a cruise and make sure that your potential roommate and you are on the same page. Some things are obvious, heavy/light drinkers, early/late risers, relaxation/active etc.
If you're a lady and don't want your room mate to bring strange men to your room before you ever even leave the port it would be wise to set ground rules. If you don't want practical jokes played on you by strange men in your room with the blessing of your roommate, it's best to set ground rules that you are both comfortable with. I didn't want to ruin her cruise by being a "prude" but I sure as heck wasn't going to ruin my cruise by rooming with someone that appeared to be solely on a man hunting mission. I packed my bag and got right back off the ship before the ship departed, lost my cruise fare but kept my inner peace.
I have since booked 3 short cruises as a solo and 1 with my DH for the rest of 2013. For 2014 I'll consider room mates once again but will be much more careful in the future. Admittedly there wasn't a lot of thought that went into the process for my failed cruise this year, a cruise is a cruise..... right? Just going to be a lot more careful and smarter about cabin mate choice in the future.