hun i can feel ur pain. my mother is also bipolar but has never been officially diagnosed simply b/c she will not get help. sometimes i think its b/c she does not believe how sick she is, sometimes i think it's b/c she does not believe she can be helped. it had a huge impact on me...i was a very angry child b/c even back then i realize i didn't have a mother like everyone elses and i was ashamed. i developped depression and b/c of my parents refusal that anything could possibly be wrong in their "perfect" (haha) family, i never got medication or adequate therapy until about a year ago, and by then it had become what they clinically term "chronic"...also developped anorexia at the age of 18, and could have died from it. once again, no therapy, everyone's attitude was just to make me eat something! so i know what u mean about the stigma, my mother is in her 50's also.
at the moment ur mother may not be hurt from ur actions, but u probably are. furthermore, with someone that sick, it's practically impossible not to hurt them in some way, everything is amplified into such a big deal for them...my mother used to cry over someone saying that there was a bone in their fish (that she had cooked)! u could try to encourage her to get help, but if she is anything like mine she will not listen to a word u say and just accuse u of being rude and ungrateful. eventually i had to cut mine off for the most part...she was just too stressful and difficult to be around and if i was frightened of what i would do to myself if i continued in this relationship. i moved cities, stopped answering the phone when she called (which was just about everyday) and basically only have the absolute bare minimum to do with her, in order to keep the peace with other members of the family. if u cannot convince her to get help, i would walk away, for ur sake. it is painful, and there was a lot of grief for me. but in the end, it is her own responsibility to seek help. u can't make her, as hard as it may be...others can help her along the way, but she is the only person who can make her better.
u may want to consider seeing a T urself, there is a lot of stress on the children of mentally ill parents and it's smthn i don't think is talked about enuf. pm me if u wanna talk