I am thinking: look closer to home. Either suicide or someone she knew. Have cadaver dogs been sent into her home, partner's car and Kent home yet?
My first thoughts when Helen went missing were that the circumstances around it were odd - that she was seen walking Boris near her home and then vanished into thin air while her partner was out on an errand. Did she return home after walking the dog and was her partner in then?
Regarding suicide, I have read that Helen was close to her parents and brother and I would have thought she would have at least left them a note if that was her intention and what about her beloved Boris? I do feel that she would have made sure he was taken care of and not harmed.
I realise that is not very likely Helen has gone into hiding or decided to start a new life, but if she has she would not take with her or use anything that could identify her whereabouts such as her car, phone, bank cards. If she had been planning this for sometime then this could explain the call asking about re-homing a dog a few weeks before.
As for the large sum of cash that she COULD have had access to from her home - well, either it's there or it isn't and I do wonder about the motives of whoever gave the police this info.
I do still hold out hope that Helen is safe somewhere and as time goes on I hope that we find out the truth soon and that this doesn't become a cold case.
If Helen really had been going to the cottage ( or anywhere else ), as per the note, then I would have expected her to go home, after walking Boris, to collect her handbag ( which is missing ) and at least some luggage, even if only a small case.
Re the cash - I also wonder how accurate that info is.