Great topic. What a great part to play on a soap opera in the mid-60's: trampy runaway wife, nasty sister-in-law, possessive mother, and a Phoenix to boot! Only Diana Millay could be so rapturous and sublime and lovable in the role. She's one of those actresses who, when playing a role she relishes and relates to in ways no other mortal being could, takes you on a wild roller coaster ride through her character's twisted passions - guaranteed. Millay was no slouch on some great episodic late 50s/early 60s TV shows (Perry Mason and Route 66 come to mind) - with the blonde hair, the mole, the sharp intensity in her crystal blue eyes, she always left a memorable impression everywhere she went.
As MB pointed out, props to the Laura storyline and all involved, for boosting the show's ratings, taking it to stranger dimensions for a daytime series, whereby ABC allowed Dan Curtis time to develop and present Barnabas Collins to the masses.