I need advise about my sister marital problem

My sister is very sick ( in my opinion) she has an affair with her best friend husband, now she wants to divorce her husband , they have 3 children, her husband still love her very much and forgive her.
The guy told her that he will leave his wife, but i founded that is not true.
I told my sister she need professionel help, but she denied been sick.
Please help, teach me what to say and how to convince her to go see a doctor or a pschychiatrist.
She had a misscarriage with her husband a year ago.

I am desperate for any help i could get, it broke my heart, because i can tell it is not my sister that i once knew.
Anyone out there with experience teach me to solve this problem, it would be very much appreciate it.

A person can go into a deep depression after losing a child before term. Oh man I can't say anymore. Not now. I wish you the best of luck and pray that she gets better soon.
Zen

<font color=green>The snow falls on no two trees alike, and the forms it assumes are as various as those of the twigs and leaves which recieve it...so one divine spirit decends alike on all, but bears a peculiar fruit in each--Henry David Thoreau

maybe you could invite her to attend a CoDa meeting (or some other self-help group) with you? http://www.codependents.org/newcom.html

it may or may not be the issue but maybe she could listen to others and somehow benefit from their struggles?

(((Huggs)))