Niche Question

I am struggling to find my niche. I’m a nurse, finishing a holistic nurse coaching certification course and building the framework for my business. I’m at the “find your niche” phase and trying to figure it out.
Niches I’m considering:
High achieving, working moms….
Perfectionist professional women …
Burned out nurses ….
who are struggling to reach their health goals, have difficult relationships, etc. I think I should leverage more of my nursing background and get more specific with health goals.
These seem pretty broad to me so wondering when targeting a specific group, for example if I choose high achieving working moms and want to focus on nurses do I include them in the niche or is that more of a marketing thing?
Would I say, I help high achieving nurses heal their bodies and relationships OR if it’s high achieving busy moms but then focus my marketing on nurses?

Also, I fit into most of those categories and haven’t figured it all out for myself – though I am trying and making progress. Do I need to figure it out for myself before I can help others?