I can see it from both sides. I don't know how recently your were diagnosed or how much treatment you have had including meds and/or therapy, but it gets to the point where friends and family believe that you should have the coping and behavioural skills necessary. Sometimes a sorry will go a long way to. Apologize for the negative effects a symptom has on others. If/when the person acts why you did or didn't do the something then bringing up the disorder is reasonable, but, if you are able, explain what help you are getting or how you intend to prevent the offensive behaviours. If you believe you cannot prevent the behaviour to may wish to bring your mother or other friend or family member to bipolar education either with your T/pdoc or through another organization.