The branches wherein you die are effectively discounted, because there is no future you who will remember your current self. The same applies to lesser degree to branches where you suffer brain/memory damage, to varying partial degree.

The problem with the whole QM suicide/immortality is that it assumes that we shouldn't care about measure, and we shouldn't care at all about universes that lack ourselves as future observers. Both of these notions are probably wrong from the perspective of normal human utility functions.