Agreed Beth, to a degree, but with some it is merely fear of the unknown that is the main reason they stay. I was in exactly the position you describe, when I walked away most of my friends, family and contacts were J.W's, I relied on them for business, also my wife had been in from birth, and I did not know if I would lose her !
But, it is so much a part of me to be a Lover of Truth that when I learned that far from being "the truth" the J.W religion is The Big Fat Lie I simply had to leave cold turkey, I could no longer be a part of that without sacrificing every shred of personal integrity, and denying who I really was !
I took my chances, of course the J.W's cut off all contact, I lost business, and my J.W family became "distant", a sort of mild shunning. My darling wife it turned out was happy to leave, she hated "Field Service" and the Meetings, apart from the socialising after.
Within a few weeks she told me she was an Atheist now too. I survived financially, made contact with my ex-JW and never J.W family, with whom I am now very close, and I made closer ties with friends I had who had never been J.W's. Those friends are wonderful, they have helped me through tough times, and their evident love is unconditional.
So PIMI's should have no fear of leaving, if they are Lovers of Truth, and have personal Integrity, but how many actually do now ?