The intensity of bipolar symptoms are different from person to person as well as one portion(depression or mania)of the illness presenting itself more clearly than another. A diagnosis is difficult to determine at times, even for professionals. In order to accurately diagnose someone, professionals are dependent on either the patient's or others interpretation of symptoms. The mania portion of the illness is at times mistaken for anxiety.
If a person acknowledges their illness, that is a good starting point. It is not uncommon for someone to be resistant to the diagnosis or course of treatment. Especially for someone who experiences the mania portion. Mania symptoms include a period of feeling high or elated and increased goal activities. It is understandable that a person may be reluctant to address these symptoms as they seem positive. Other individuals see these effects as positive, at least the initial stages, and are reluctant in addressing these symptoms. Unfortunately, these symptoms get worse and could turn into psychotic episodes.
The goal would be to get the individual to see these patterns and buy into the illness. This could be done through readings or meetings. I would suggest The Bipolar Workbook:Tools for Controlling Your Mood Swings by Monica Ramirez, Another good book for families is: The Bipolar Survival Guide: What You and Your Family need to Know by David Miklowitz. To find a group, you can go to www.meetup.com or look through your local paper and\or Hospital.
Most of the time, someone with this diagnosis is going to need professional help. Either medication, therapy or both. If the person is reluctant to buy into the diagnosis or refuses help, I would suggest talking to a professional to find ways to intervene. If the person is close to you(husband, wife, partner), engaging him/her in counseling and addressing the symptoms you see and how it impacts on the relationship could also be a start. Present your concerns to the therapist and hopefully this will enable all of you to be on the same page.