Since I don't have an "X" husband it's kind of hard to think what I would do. What I THINK I would do is this. See exactly what pattern she wants to use. Then on your own scrap fabric show her how to cut it and then tell her to use 1/4" seams when she pieces it for the top. Tell her what kind of batting to use and see what backing she wants to use. Again...show her with your own fabric how you make a quilt sandwich. Is she planning to stitch in the ditch or FMQ or send it out to be quilted. Oh...and binding of course...again show her on your own scrap fabric. I consider THIS helping...and not doing it for her.
Did she specify what she wanted from you...strictly guidance or does she want you to actually have hands on sewing/quilting for your X?
I guess a logical question too is...how old is your daughter? If she is really little then I would probably consider the hands on approach. But if she is a teenager or older then I would go with the guidance approach.