Being a single mother, she had a quite busy work schedule, so from the moment she woke up to the moment she went to bed, you'd better not waste a single minute of her time needlessly.
I was a working mom too, not single but my husband was disfellowshipped, plus couldn't keep a job. I once sat down and calculated it out; with my job, cooking, cleaning and the meetings, study, service, etc. , if I did everything I was supposed to do I would have five hours a week to call my own. I sort of gave up at that point, I realized I didn't have it in me to do it all.
I used to feel guilty that I didn't have a regular family study, while many of my friends were much more disciplined. I thought their children would stay "in the truth" while mine might not, but what happened was that most of those children didn't actually stay either.
In seemed to me that those children were either religiously inclined or not and the parents had limited influence no matter what they did. This religions is all or nothing, if you don't attend meetings and go in field service, you don't count, and many people just aren't going to do all that, which is probably why they have such a low retention rate.