I have seen a great deal of negativity towards Amelia Novak, and while it's unsurprising considering the fandom, it's still alarming and saddens me. After reading the reasons people have given to rationalize their dislike for her character, I feel the need to comment on them since I think her character needs some kind of love and defense.
We don't know much about the Novaks. The episode, 4.20 "The Rapture", was meant as a backstory for Castiel's human vessel, which did include his family although not enough to know every little detail. The assumption that Amelia was just as religious as Jimmy is just that, an assumption. We don't really know for certain how deep in her faith Amelia was, or how she would react in the same situation. I feel that people are oversimplifying things by suggesting that she should have believed Jimmy, that she should have been behind him 100%. When she saw her husband have his hand in a pot of boiling water, there must have been a thousand things whirling around in her head right then, and when Jimmy said that it was a miracle and that he could communicate with angels and that he was chosen? Can you imagine what was going on inside her head at that moment? This isn't a question about her faith or how religious she was that she couldn't believe him, it was a matter of what would really happen in this situation? Most would be in shock, in disbelief, trying hard to understand what was happening and why and ask for explanations and so forth.
To me, Amelia's reaction was entirely believable.
Then there's the whole argument when she forced him to seek psychiatric help and threatened to move out with their daughter if he didn't, because clearly she's a "horrible bitch" for worrying and his and their daughter's safety, amirite?
First of all, humans aren't perfect. We're contradictory beings and we make difficult decisions and choices underneath certain circumstances that we may not like. I believe that Amelia was thinking about her family's safety, she wanted her husband to be okay but was worried about what else could happen that might endanger their daughter. This is placing her underneath a difficult position, as a mother and a wife, who is witnessing something that she can't explain (again, this is not a question regarding her faith compared to Jimmy's.) She was using tough love which I believe was a last resort for her, and she clearly didn't like it. She was crying in that flashback scene, for goodness sakes. But she believed it was the best thing to do, because she couldn't handle it anymore. Does this make her a horrible person? Of course not.
It's interesting to me how many are quick to claim, "oh, I would have believed him!" -- it's easy to say that when we already know what is going on, however when in reality you're faced with something like this it's a completely different tune. Everyone reacts differently to a situation. Some might believe, some might not. Some might even take a while before being convinced of anything, and some might be scared shitless. The thing is, we can never predict how we will react to something.
Also keep in mind that we don't know everything there is to know about the Novak family. We only got a glimpse into their lives, saw bits and pieces of selective scenes but we don't know the whole story.
Can people be irritated at Amelia for not believing in Jimmy at first? Of course, since we the audience know what has really been going on it's only natural that we would feel slightly more defensive on his side of the story and wanting her to be just as convinced as we are. However, to call her vicious names and outright hatred? I feel that is uncalled for, particularly for a minor one-episode character.