Stuck – really stuck.. VERY Stuck!

My Question: If someone has a deep passion for several areas of “niche” work, what is the best course of action to decide on one or two to narrow it down?

A little background:
I had a wonderful childhood filled with many obstacles. These have proven to be the best tools for being a very resourceful and hard-working person. There was all types of abuse, young. There was being told I was not worth anything, etc… I could go on but I would never waste time so frivolously lol… !!

I married a man who is pretty challenging, to say the least… he was in the service for 30 years and now has 3 forms of cancer; he has pretty severe PTSD and he refuses to get conventional treatment for. He is extremely angry. He displaces his anger and it ends up on me mostly. I have been patient, understanding, constantly the positive upbeat one who tried to be Polly Anna which he seems to hate.

I have been blessed to understand the meaning of staying in shape, despite the averages for Americans, aging, etc.

Ok… sorry this is really long but I promise I am. getting to a point here!

I have an MBA and a Six Sigma Black Belt/ I love productivity, time management, and reducing waste in business.

I have experienced so many things in my life-

I know I could focus on military spouses — helping them
Helping businesses thrive through coaching their employees
Helping adults coping with abuse-helping them understand how to use the model to put it in the correct place
Helping people lose weight and get on a great path to healthy eating, lifestyle, etc.

With so many areas, do I not focus on a niche? How do I choose what to focus my coaching business on?