Dear Lostfamily
How old are the kids? Mine are now (after 16 rehabs) saying that they want to wait a bit before they see him. They are 9, 17 and 19. They use their own voices. And I respect it now. Regretfully I have to add that I forced visitations with them before- when they were not ready to see him. I chose to rescue him rather than the children.
If they are younger it is more difficult as you must be their voice. All I can say from my experience is that visitation or not cannot keep the alcoholic sober. It cannot be used as motivation. Nothing can - but for her wanting to get better for herself.
Maybe work with her therapist.
Sorry for your dilemma
Hugs