Not all show "monster" behavior. Mine never did towards me.
Although there are many similarities, each situation is different as well.
Remembering that their crisis is not about you and not about your marriage helps to navigate through these tough days. And it is really heartbreaking for the LBSer.
I have read a few thoughts from the person in crisis that "they felt they had to leave or they would die". They are having a major crisis of epic proportions and we unfortunately are collateral damage.
It is really hard to see this person we have loved morph into someone that we don't recognize, whose actions and behaviors go against everything that they once were. MLC seems like a very selfish and impulsive time and confusing, both for us and for the MLCer.
As Ursa said :
The reasons that the Mod-lifer has for being unhappy at 10:00 on a Friday will likely be different form those at 10:25 on Saturday if you get my meaning.
This "changing their minds" is confusing and normally, if there is a problem in our relationship, we talk, argue, find a resolution....in MLC, there is no desire to resolve whatever it is that is making them unhappy, because as I said...it's not us and not our marriage.
Their actions may not be "kind" but remembering that they are in crisis helps us to step away from the insanity and see that it isn't just to us that they have changed so dramatically. They walk away from other family members, children even pets. They build friendships with people they would never have been friends with before.
There is nothing we can do...in some respects they are "lost"..whatever caused them to go into a crisis is a real "event" that has created tremendous chaos in them...and for the ones who share what it was like for them, many will say they have no clue why they did what they did.
I don't know what to call it psychologically, but there is some kind of break in their psyches. In my mind, related to things that happened way before we ever knew them.
Take care of yourself. Talking to her about things other than your relationship is fine if you are ok with that.
You'll get lots of different advice here. You can sort through what applies and this is a time of deep reflection of who yo are and how you want your life to be.