My question involves collection proceedings in the State of: Florida

Recently I lived in a house rental with my girlfriend and a friend of hers. After being there for a little over a month our friend decided she no longer could live out and because my girlfriend and I could not afford the rent only split two ways we were forced to break the lease. Our landlord was nice enough to simply terminate the lease and only charge us the initial deposit. My problem however is our bills (water, electric, cable and internet). We still owe for the last set of bills and our third roommate is refusing payment. This is an issue because all of the bills are under my girlfriends name, thus affecting her credit. Plus, my girlfriend initially payed for the third roommates original deposit ($290) and has only payed her back $200. All in all she owes us several hundred dollars in bills and payback. The problem is, because she was a friend all of this was under verbal agreement at the beginning of the lease (all bills and rent split three ways evenly). I have done some research and found several sites to be of help.... mainly this following link...

http://www.ehow.com/how_4905268_collect-money-owed.html

However she doesn't seem to cooperative in paying off her portion of the bills. I know it's only several hundred dollars but that is money my girlfriend and I just can't afford to loose. I want to remain as professional about the situation as possible, incase I have to take it to small claims. Lots of questions, so any guidance will help. Also, would I be able to collect our portion of the lost deposit ($292 each, my girlfriend and I), since she was the entire reason for breaking the lease? Could we hold her responsible? If not, my main concern are the bills.