It's innevitable, they will feel bad to some extent, depending on quality of your relationships with them. If you don't want to hurt them TOO much, then you should give it a time and gradually move away from them, in other words cut all ties with them. Which can be pretty hard to do, because they could try to stop you from withdrawing from them if you're not committed enough. And as I said, you need a lot of time. Idealy you need to make them forget about your existance and do ctb only then, so they would learn about it only after some time after your death. But that doesn't spare them from the thoughts like "could i do something to prevent this" anyway, if the some person really liked you. All in all this doesn't seem realistic, but I guess it's the only way to get close to the needed result.