Pearls before swine

I am trying to train a new choir director at church. It has not been going well, but we are doing our best to accomodate everyone's circumstances. She hasn't been very open to my offers to help her learn to lead correctly, but I know it is partly because she has a very busy schedule and her health isn't always the greatest.
Now all of a sudden she wants to have input into the music selections. This is a good and a bad thing. I had been hoping she would take an interest in helping to select the music, but she could have spoken up three months ago when I chose the Christmas music for this year!! She also informed me that songs with multiple parts running at the same time (ie. 2 or more melody/lyric lines) just sound like a big jumble of garbage. Gasp! I didn't even know how to reply to that one - some of the most powerful music I have heard is in this format!! And, since she doesn't even always make it to practice, we have been working on just such a song.
Fortunately, I think I can work around this problem. Most of the music we sing is just regular four-part choir. But at the same time, I try to be open to suggestions and we are doing songs I don't like because I know that other people do like them. Why do people have to be so difficult??!