I totally respect people with BP who make the decision to not have children. It is not just people with Bipolar. Lots of people forgo parenting for various mature reasons.
But you don't really know what you can and cannot do because you are not treated. I have been with my husband for ten years and I have two fantastic children and one more on the way. I only got my dx three years ago. I could not do this without treatment. My children are the number one reason I went on medication. They are the number one reason I do all of the lifestyle stuff I need to do.
But here is the thing. Most people with Bipolar struggle to do Anything without treatment. The Family is just another part of it.
Btw. I totally disagree with the comment about BP 2 being possible more manageable without meds. The depression is the same and depression is deadly. I held that belief for awhile that a "lighter" Bipolar was more conquerable. But it isn't. It will kill you just the same if you let it.
Get some good treatment and then you can decide what you can do. You might be surprised how stable you can be