I can see it happening, definitely. EE have had characters brought together by grief before (Jane and Ian in aftermath of Lucy's murder). I can see Honey becoming indispensable, being brilliant with the three kids - and Jack, in a haze of grief, just being drawn to her sweet, kind nature.
Honey would most likely fall very hard for Jack, but Jack would want to back out after a few weeks and go after his usual hard as nails gangster type.