Heather - some grat advice here. I have beenreading along and find your sister and mother's attitude at the same time unbelievable and all too credible.
Are you familiar with the theory (R.D. Laing I think (not KD!) that dysfunctional families have to scapegoat a family member? Lots of reasons - it bonds the others and takes their attention off their own problems and dysfunction. If you cease to be 'dysfunctional' then you are a threat to the stability of the family. They do not know this consicously of course - if they had any self awareness or emotional intelligence they wouldn't be doing this stuff.
They hurt you, and I am sad to say, they get some sort of buzz out of doing so, which they strenuously deny under the guise of being for your own good. Really, really? Is criticising and belittling someone a helpful course of action?
The New York job sounds good - it would get you away form your toxic mother. At a distance you can be an exemplary daughter - regular short phone calls, and to your sister.
Now for a small 2 x 4. (And I learned this from personal experience of a very very difficult r with my brother) You allow yourself to be set up for this. For example at the restaurant, you would have left, with a sweet smile and the need for an early night.
I wanted my brother's approval and love, I really did, and I set myself up for so much unkind treatment. Until I changed the rules, not by saying anything at all, but acting differently. We had almost no contact for years, and then he started pursuing me. When he did, I was different, I had changed, and when he occasionally tries his old routines they go right over me. I honestly think we are both happier for the changed relationship.
I thought there was something wrong with me because we didn't get along, and this was a belief that my otherwise very kind and loving parents fostered. The only thing that was 'wrong' was my need for his approval and his use of that need to be unkind, dismissive etc. I suspect he would say that the reason we now 'get along' is because I have changed!
Heather, you need distance and space from these people. They are controlling and problematic. They have cast you into a role which they need, and want you to remain there.
There is nothing intrinsically wrong with you, but the need for the approval of the 'lions' who are trying to eat you isn't doing you much good (to use your own analogy)
