Your personal problems with co-tenants are not the landlord's problems. You will all be personally liable if landlord (or utilities) go to court for any unpaid balance of rent and damages to the premises. Good idea to see attorney in your area about your options.
The above answer is generalized reply to an question and is not intended to be legal advice or establish an attorney-client relationship with you. If necessary you should meet with an attorney and provide the attorney with all relevant documents and get an attorney opinion or advice on your situation.
As my colleague said, your obligations to your landlord, including the obligation to pay rent, is independent from your agreement with your roommates. You may get permission from the landlord to sublease; I don't see how your co-tenants can place any restrictions upon you in addition to those already in your lease with your landlord.
That being said, please consult with a local attorney. You have a lot going on in this situation and may have legal recourse against your former roommates.
DISCLAIMER: Brandy A. Peeples is licensed to practice law in the State of Maryland. This answer is being provided for informational purposes only and the laws of your jurisdiction may differ. This answer based on general legal principles and is not intended for the purpose of providing specific legal advice or opinions. Under no circumstances does this answer constitute the establishment of an attorney-client relationship. For legal advice relating to your specific situation, I strongly urge you to consult with an attorney in your area. NO COMMUNICATIONS WITH ME ARE TO BE CONSTRUED AS ARISING FROM AN ATTORNEY-CLIENT RELATIONSHIP AND NO ATTORNEY-CLIENT RELATIONSHIP WILL BE ESTABLISHED WITH ME UNLESS I HAVE EXPRESSLY AGREED TO UNDERTAKE YOUR REPRESENTATION, WHICH INCLUDES THE EXECUTION OF A WRITTEN AGREEMENT OF RETAINER.