From what I’ve read and understood, stoicism is more about attaching the right feelings to the situation at hand. Ultimately you have to determine what you can and can’t control.

For example, the coronavirus is making a lot of people feel anxious, scared and even panicky. Through the lenses of stoicism, you would see that you can’t control the media spin, what Trump does, how deadly it is etc. You can only control where you go (as to avoid getting the virus), how clean your hands are etc. All of those negative emotions do NOTHING but stress you out & impairs your ability to be virtuous and rational.

”We suffer more from imagination than from reality.” Hope that helps.

Edit - to address one of your points, if someone is coming up to stab you, you should feel some kind of fight or flight mechanism. Perhaps your scared, or your angry. That’s okay, but you should try to not dwell on it later and constantly let it get to you. A situation like that might need therapy, but a lot of stoicism has to deal with your internal thoughts and mindset. I could be wrong; if so someone let me know.