The more I think about this the more concerned I get. I hope you are not labeling this woman with an autistic son a jezebel because she can be obnoxious or irritating to you. Autism is a very difficult thing to live with. How can you see inside her heart whether or not she is devout? Maybe the pastor is completely innocent (you said he seemed interested intellectually) and he has other reasons he speaks to her a lot like for some political church reason like tithing or something else. I am not saying these things to knock you I just hope that you may be wrong and I guess it depends on the denomination you are part of as far as the other woman that said she saw a jezabel spirit over your head.
p.s. I am sure she is sad and alone that is part of being a parent of a child with autism-not to mention being divorced. She probably talks a lot to the pastor because she is and maybe he knows this also.