In these situations one has the one physical
body but more than one person wanting to use it. In other words the person
who was born with the body (the owner) has others (usually discarnate)
trying to, and
sometimes succeeding in, getting control
of it. As each person (personality) takes over partial/whole control then
the physical body takes on a different persona. For people who are only
looking at the physical form it appears that it is displaying multiple
personalities. They then sometimes think that the owner of the body has
some sort of "fragmented" personality. This is incorrect of course but
unless one is clairvoyant one could make this incorrect deduction.
To remedy this situation the owner has to regain ownership of their own physical form and eject the person(s) who may be competing for it's use. This process is generally called "exorcism". There are a number of ways to do this. The person themselves and/or others, (preferably both) can imagine the physical form being filled up with a very hot, bright, golden (or white) light. One can also pray for help from Divine Forces to aid in this. Once the person regains more control of their physical form then they need to learn about/apply psychic protection techniques. To avoid a repeat situation in the future.