Timeshare rip off

Illinois but the problem exist in Florida with a timeshare that was purchased between two people that are not married and have since separated. Westgate is still taking monies out of a at the time joint account, now it is just mine and my partner did not want it in the first place. How can I end this nightmare and not have to keep paying for this and mess up my credit because I really can not afford it. I am out of work and have a small child to support. I truly need help and I am stuck here. I also received the maintenance bill a week ago and they are charging me $525 plus a tax of 20% which brings the total to $626. How can this be such a charge? I can believe the tax that they charged, is that legal? Someone out there please help me.