Now, MLCers are impervious to reason. Validating (which works for some MLCers and not others) isn't reasoning with them. It is simply acknowledging they have a point of view (OK crazy, but not to them, at that point in time, from planet Zog)
So validation would be more, I am sorry that you are upset by this, or I am sorry you feel that way.
With some MLCers a follow up question might be attempted - what would you like to have happen in future? But this can backfire because they have to move from blame to reason, which is a tricky manoeuvre for a MCer.
I know I sound patronizing, but you have to treat them like either small and very tired and unreasonable toddlers, or moody and aggressive teenagers, and it isn't always clear which one you are dealing with.
In either case, reason and explanation does not work. If it did they wouldn't be MLCers