You are the same person you were before being diagnosed bipolar as you are today. What did the diagnosis change? You now have a label attached to a constellation of symptoms that psychiatrist know how to treat. Develop a trusting relationship with both your pdoc and therapist. If you don't have either one, my advice is to start shopping around.

What scares you about having bipolar because you sound frightened to me? While there are some aspects of the disease that are troublesome, by and large once you get meds that work and a therapist to help you, it becomes just like any other chronic illness. Yes, you will likely need medication for the rest of your life but so do diabetics and others with some types of physical illnesses. A mental illness is really no different.

I'm not going to lie, there are acute phases of bipolar which can really be painful, but again there are painful acute physical injuries as well. Hopefully you will be able to find a mix of meds, therapy, and lifestyle choices that minimize these acute episodes so you can have long stretches of stability.