I'm a MWI cynic*, so here is my approach.
There is an interpretation of quantum mechanics called the many-world interpretation that rejects the wave-function collapse of the classical interpretation.
This interpretation leads some people to the belief that all possible alternative histories are real. Everything that can happen does happen. They assume that if you die in this world, you would also continue living on in another world. Since there must always be a chance you won't die, then there must be a world in which you live forever.
The problem with this belief is that at best it applies only for simple quantum systems, and generally not to events as large and complex as a person's death. To avoid death, a very large number of quantum level alternatives have to be simultaneously selected for. The probability of this simultaneous selection will be effectively zero.
In MWI terms this means that you die in all worlds, except the impossible ones.
Value the life you have and don't depend on quantum immortality.
* I like the MWI on lack of wave-function collapse and on quantum decoherence, but I don't think that the idea of separate worlds is necessary.
Eh not impossible... just very improbable (in a given world) and certain across all worlds.
I would have thought the more conventional explanation is that the other versions are not actually you (just very like you). This sounds like the issue of only economists acting in the way that economists model people. I would suspect that only people who fixate on such matters would confuse a copy with themselves.
I suspect that people who are vulnerable to these ideas leading to suicide are in fact generally vulnerable to suicide. There are lots of better reasons to...
I had an incredibly frustrating conversation this morning trying to explain the idea of quantum immortality to someone whose understanding of MWI begins and ends at pop sci fi movies. I think I've identified the main issue that I wasn't covering in enough depth (continuity of identity between near-identical realities) but I was wondering whether anyone has ever faced this problem before, and whether anyone has (or knows where to find) a canned 5 minute explanation of it.