Denise,
Has anyone explored the possibility of hyperthyroidism in your
leaking-post-weaning mom?  Hyperthyroidism can cause a great increase in milk
supply, and will also predispose to weight loss.  I beleive other sx are heat
intolerance and pressure behind the eyes that can lead to exopthalmos
("pop-eyes").  It can be very tough on the mother's body to have the
metabolism going that fast.  I have also heard of a very dangerous thyroid
condition called thyroid storm occuring in nursing women.  Diagnosis is simple
via blood test.  You could talk to her new doc yourself, you might ask him/her
if he/she is concerned about your client's thyroid function with the copious
milk supply and weight loss.  The continued amenorrhea is probably related to
whatever is happening hormonally as well.
Keep us posted!
Catherine Watson Genna, IBCLC