Relationships and Coping Community

I am the oldest of 6 children. I am 23 and have graduated from college and am living in my own apartment paying all of my bills except for my car insurance and cell phone (my parents pay for these) I just got engaged and am going to be married in about 8 months. (August 2013). The only thing in mine and my Fiances relationship that causes consistent tension and arguments is my parents. They are extremely overbearing and controlling and do not ever attempt to view the world through another persons eyes. With them, it is their way or I am being selfish, and I don't care about my family.

Dealing with my family has been something that I have just put off. I hate it when others are disappointing in me and if I do not do what they want, that is exactly how they act.

This year they asked me when me and my fiance would be coming fore Christmas (I live an hour and a half away, and already drive that distance every Sunday to visit and be in their church) And I told them that we would be there on Christmas morning and just stay for the day. Immediately my mother started 'offering suggestions' to come on Christmas Eve instead and said how dumb it was that we would want to be alone instead of with family. I expressed to her that it was not a lack of desire to be with family, it was simply more convenient for the pair of us, and we were just going to have dinner and exchange gifts. That was an unacceptable response to her and she has continued (Even this morning- Christmas Eve) to tell me how I am acting as though my family does not matter.

I know that tonight all they will be doing is watching movies. It isn't going to be a time of any specific tradition, just 'family time'. I have nothing against that, however my fiance is working today (his 8th straight day) and we would really like to just relax and not drive down tonight. We both feel that my parents are being unreasonable and that we should be able to come and spend Christmas day without causing an argument.

However, my mother now has blamed this 'non family oriented' behavior on the influence of my fiance. Perhaps my steadfastness is due to him. However, this situation is not. Whenever I do something that is not what my parents want, my mom guilt trips me and manipulates me to get what she wants. I asked he when she would start treating me like an adult ad respect my decisions and her response was "when you start making the right decisions, ones that arent ridiculous."

How do I change this unhealthy and controlling relationship to one that is appropriate??