Hi Andrea,
I really wasn't sure whether to try to respond to this. I suppose because it could impact or broaden the discussion of PL memories and tendencies in relation to mental problems in ways that are very unusual on the one hand and are pure speculation (by me) on the other. Also, I am going to have to display my own minute level of knowledge in terms of psychological phenomena. But, fools rush in . . . so, here goes: I have long assumed that PL personality traits may form unassimilated parts of the unconscious self that are rejected due to their lack of congruity with the current lifetime and current life persona. This leads to problems . . . .
This is, btw, merely an expansion of the general Jungian idea that one of the big goals of life is "individuation" which involves assimilating the parts of ourselves that we initially reject and push into the subconscious. This is the half-baked explanation of a very amateur Jungian, so take it with a grain of salt. In any case, to the extent I understand the process it involves dealing with the "Shadow" which is closer to the surface and then the "anima" or "animus" if we are, respectively, male or female. This is not the end of the process, but that's enough for now (besides I am quickly out of my depth on things like this). Anyhow, the question is where do these "rejected" part of ourselves come from?
The usual answer is that they are, at least at the very beginning, inborn. This should be a clue to where I am going, as someone who believes in PLs also believes that a lot of our inborn traits have been developed in PLs and sometimes over several lifetimes. So, what happens to the traits you developed in your lifetime as Napoleonic Grenadier, when in your next life you are born and raised to be a Victorian lady? Mommy and Daddy are going to punish and scold when you attempt to gut your little brother. So, a young Victorian lady is most likely to repress these no longer socially acceptable impulses. (One of the most prominent human tendencies is the tendency to "go along to get along" and a small child vs. parents and society has very little choice in the matter).
This doesn't mean these traits have been wiped out, they're still there and are likely to show themselves in unpredictable and negative ways. To go back to some earlier lingo, they are now parts of the Shadow and Animus that need to be brought to the surface and assimilated in a "healthy" way. This is far easier for the modern woman than for the young Victorian lady in the example given, but you see the problem. Anyhow, I'm no psychologist, but this might be something like what is happening with your mother. Just an amateur guessing . . . .
Cordially,
S&S