I think you're absolutely right. When you're absolutely blindsided by grief, and perhaps not getting the support you'd want from friends and family, it makes you very susceptible to small acts of kindness. So he'd have known that and taken advantage of it. I disagree, though, with some of the newspaper commentators who have said she was naive or too trusting, because you can't go through life constantly being suspicious of people who are nice to you. Stewart didn't have a criminal record and there was no evidence that he was ever violent to anyone. Maybe she should have been wary of gold-diggers, but I can't see how she could have been prepared for the possibility that a man would seek out a relationship with her purely so he could murder her for her money. After all, how often does that happen?
There are loads of things that still puzzle me about it all. One is the lie Stewart told about the "note" - it would have become obvious to the police after a while that Helen wasn't coming back, therefore increasing the likelihood that Stewart had made up the story about the note. Also, if your partner had left a note stating their intention to go away for a few days, wouldn't you hold onto it rather than throw it out? So it was a stupid lie to tell, which lends support to the suggestion that he hadn't originally intended to kill her that day, but something happened to make him panic.
All the early reports of her disappearance mentioned the note - the police never said, "We haven't actually seen a note". Last May the chief inspector then in charge of the case did an interview with the Guardian in which she refused to say whether the note was handwritten or typed. It was only at the trial that it became clear that there had never been a note. It made me wonder how soon the police cottoned onto the realisation that he was the killer.
