The support group sounds like a good idea

It is unlikely that your mother can change the way she interacts with you even if she really wants to. (which I bet she does) The task then will be for you to find a better way in which you respond – vice react – to the experiences, memories, resentments, frustrations, fears…  It is possible. Focus your care taking skills on yourself. Eventually as you work on it you will notice that you can view an experience without attaching your sense of self to it. You can feel sad without “being” sad, you can feel frustrated without “being” frustrated… When you get to a place where you really ‘know’ that difference of feeling and being you will find that you have created a safe space for yourself and I would bet some creative impulse emerges. When it does show up be courageous, no judgments, no labels just follow it and I think you will surprise yourself.