Hi Avocado. I'm not sure I understand your post.
If subways are your main trigger, and there's no way you will take them, it seems you've made a decision and that your mind is closed to the idea. The choice is yours to take buses if you prefer, though it make take you longer to get to your destination.
If you want to question it and get help in changing your mindset so that you can eventually ride the subway, then think about your mentioning that things often happen there. Ask yourself how often things do really happen though, what kind of things exactly, and at what time do unpleasant things happen. (usually late at night?) What about all the people who successfully commute that way every day to and from work without any problem? It might help you to look at the safest times, and see the stats on those?
Are you following the Panic Program?