There are a lot of comparable symptoms between BPD and MLC and they are very often confused for one another. The bigger difference with BPD is that it is there for a lot longer and the chances of coming out of it without counseling are slim to none. In MLC a shocking event may cause the problem and then another shocking event (say spouse moving on) may wake them out of their funk. Where in BPD the second shock usually has little or no affect. Usually BPD has an associated disorder like extreme narcissism or attachment disorder.
In all the reading I have done, while MLC is a mental problem....it is nowhere near the mental problem BPD is. There are boards around on the net for spouses of BPD people and I would venture that a divorce rate follows the disorder in the tune of 80-90%. A big indicator of BPD is the spouse referring to life as "walking around on eggshells" in that they can never seem to please their partner and are often highly criticized for everything. Usually another indicator for you is the family that acts differently when the BPD spouse isn't around....because it is the only time they can successfully relax. It is really hard to explain as most people see this behavior in their lives, but it is really extreme in it's actions.
