About 2 years ago I changed my name. I specifically changed it to something not too different (perhaps this is where my problem is...) to help make it easier for others to get used to; e.g. from Tom to Tommy, Gertrude to Gertie... you get the idea. I have always hated my birth name and finally decided I ought to do something about it!
I have always felt that if someone asks you to call them something, you should try and do so. Am I BU to ask that people will at least TRY to use my new name? (Not that it's very new anymore!)
Some do try to, and some have only known me by my new one which is usually fine (although inexplicably some of these people will use my original one which is NOT MY NAME and they've never heard it, so WHY?!...) but the list of people who have actually refused to or simply don't try include mum-in-law and sister-in-law, my parents (I kind of understand this but it's still frustrating), and all but one of my siblings. The one who does use my new name used to use it as a nickname when we were younger anyway, so I think that's the only reason.
My parents, MIL and SIL all said "oh, I couldn't do that" when I originally told them I'd like them to use my new name... 
I haven't changed it by deed poll yet but I hardly think that'll make a difference, since none of these people know whether I have done or not!!