While on the run, David marries two other women. By the time the King dies, David had other wives also, totally six sons born of different wives.

This is in the Second Book of Samuel, as David orders for Michal to be returned to him, her current husband weeping at her departure.  Go figure, but it does appear that over these difficult years Michal had gone from truly loving David, to being not that fond of him at this point ...seemingly embittered with disappointment, and of course, the evil influence by her father over the years couldn't have helped much.