If you set up rules of engagement BEFORE you're in a violent encounter, then a lot of your ambivalence about carrying a handgun will go away.
1) Learn what justifies the use of lethal force, and what doesn't. Learn those principles by heart. Then, don't draw or shoot unless its justified.
2) Learn what really happens to people who defend themselves in a violent encounter. Be ready for the aftermath.
3) Decide beforehand whether you're willing to defend only yourself and your loved ones, or if you're willing to step into third-party situations.
4) Learn to study people's actions and words to help determine whether they represent a real threat, or if you're just experiencing "bare fear".
5) Learn what kind of situations can be solved with your handgun (what shots you can and can't make reliably). Get better at the shots that you really think you must be able to make, and, maybe more importantly, learn to NOT take the shots that you can't make reliably.
If you haven't though much about these topics, the best place I've seen to get started is in Mas Ayoob's MAG40 class.
https://massadayoobgroup.com/events/category/mag40/