#4 is a definite!! That is the kicker...the easiest way for your H to legitimize what he's doing and gain support from others if he's actively seeking it...
See the L- start seeing a bigger picture...do not let H take you down...if you start to look weak and emotional- which, unfortunately is a natural response- you will make his decision for him.
Take care of the little ones, be the best Mom you can be, and take care of yourself...