On the second question, maybe checking the NPC's attitude can help you determine if she's going to attack you. The message box that appears when you move the mouse over them.
You know, most NPCs with negative attitudes will actively attack you. I've found that NPCS with a positive attitude toward you won't fight back even if attacked. Neutral NPCs are a little trouble, and I try to get around them while avoiding possible attacks. If she ignores me, I'll wait until she walks away, then bypass her.
Also, most merchant NPCs will not actively attack, if they get in your way, you can add them to the "pass NPCs" button list.
sorry, English is not my native language. I hope it will be helpful to you.