I'm sorry this woman treated/treats you this way. I'm not going to say don't take it personally (ok I am lol), but since I would feel the same way I wouldn't be following my own advice. I think this would bother even those w/o "mental issues".
This really isn't about you as much as it seems like it is. This woman appears to be very controlling. She would probably treat anyone with your job the same way. Some people just seem to live for drama or to be able to show others up. I've been in close relationships with toxic ppl and nothing seems to make them happy. Except they are happy in a sick way when ppl supposedly disrespect them so they can stay bitter and angry at the "human race".
Don't leave your church b/c of this woman/situation. I agree talk to your pastor. Also, she may really not like you just as an added bonus lol. Unfortunately not everyone likes us. Why? Who knows, but doesn't make you any less amazingly lovable.

PS I can't help, but think of WWJD? I just don't think he'd lambast you for your not having the coffee ready.