Beth Latimer character could not be that one dimensional

I can understand her initial reaction to Ellie Miller, i.e. her outburst to Ellie that she must have known something. Ellie was in shock, she had been betrayed by Joe Miller, Ellie's husband.
But for Beth to keep up that hatred of Ellie for months afterward is just nuts. Beth didn't even know her own husband was having an affair. And everyone could see how horrified, shocked, and sickened Ellie was to find out about her husband Joe.

After some time had passed after the initial shock Beth should have come to realize that Ellie had no knowledge, and that Ellie was disgusted with Joe, and was heartbroken over Danny.

Naturally the writers want characters to be very emotional. Drama is what drives shows. Nobody watches boring shows. But they ought to strive to make characters more believable.

So Beth shows up at Ellie's house to confront Ellie who is in front of the house keeping guard to make sure that guy doesn't leave with Claire. Beth comes screaming at Ellie who turns to speak to Beth and try once again to console Beth. Beth's water breaks and she screams at Ellie "see what you've done! Get away from me!"

The way they wrote Beth is so one dimensional. People don't hold that level of emotion for months at a time.