Yeah, I think she's primarily jealous of Richard's close relation to Tommy and possibly sees him taking over the role that would be Jimmy's if he was still alive. At the same time, Richard's falling in love is seen as a distraction by her from the job he's doing for her. We've already seen her being a dominant and capricious boss to the girls. Anyway, her actions have resulted in pushing Richard away from her to the point where he apparently plans to kill her.
Great episode. Nucky on the run was very exciting and also insightful. We saw that he still has some decency (trying to save Eddie, storming out in what must have looked like certain death to save his nephew). Chalky's loyalty was also quite impressive.
I loved Capone's appearance at the end.