The question is what is it that is supposed to survive? My personality? Personality and mental abilities change a lot during one's lifetime. What would be the personality, for instance, of someone in Heaven who died as an infant? The personality they might have had as an adult is unknown (since it would have been influenced by events that never occurred) and does not exist. Are they condemned to an eternity of happy gurgles and being fascinated by their socks?
Similarly, if one has brain damage, Alzheimer's, dementia etc the personality changes. Does such a person have to live in the afterlife in a state where, e.g. they can't recognize their loved ones? If not, how far does God rewind the tape until He gets to your 'essential' personality?
If you have a personality in the afterlife then it would be rational to commit suicide in your 30's or 40's at the latest, otherwise you're trading a few more decades on Earth against an eternity of life after death with a personality whose abilities have begun to decline.
But if I subtract my personality, what remains of 'me'? Given that aging and degeneration of the brain seems to affect the ability to remember (and of course death is total degeneration of the brain), no body + no personality + no memories = no person. If something survives (an abstract consciousness, a soul), there would be no continuity of experience between that entity and myself, so there is no reason to designate it as 'me'.
The idea of survival after death doesn't really make much rational sense to me. I think it is mostly wishful thinking (holding on to control and to the gratifications of this life) and a defense against certain powerful emotions, such as fear of complete annihilation, the painful feelings of anticipating the loss of all gratification and pain/powerlessness/rage that evil and senseless suffering will never be atoned.