With the fact that characters not present at an event can approve or disapprove, I think that's just a matter of abstracting the fact that characters woul hear about stuff when the group meets up in camp again. Otherwise you get a situation where you can do a bunch of evil things and still have good characters be totally okay with you just because they weren't there. It's not perfect, but I don't know what would actually be a better approach.
It is not something that needs abstracting, I think. Back at the camp there is time for talking things through. It is a perfectly good opportunity for characters to make their opinions on things they heard about known. Such moments can also be used to expand on the reasons for approval/disapproval.
Or your companions not being aware of your evil deeds could also be OK. Keeping your evil ways secret will make them extra evil! Isn´t it just like real life?
