You don't necessarily need to do a full legal name change. I changed my name by just telling others to call me by the name I preferred. Granted since I didn't change my name legally I still have to go with my legal name (which I have a very hard time saying sometimes) when I do official things like the doctor and whatnot. It can be a pain but the people I care about outside my family calls me by my new name and it has worked out very well for the past three years or so!