Forgot to add she'd have tied the dog up so it couldn't follow her at least, even if she didn't care if it ended up run over, etc (doubtful), if she was leaving of her own violation?
A massive stretch of the imagination by all accounts to think she committed pseuicide and did leave of her own volition.
Much more logical to persue a line of enquiry that she was abducted, and probably murdered by now, alongside the river theory until it became apparent there was little evidence of that and they did start searching the river on the 1st day. Expert says she wouldn't have moved far.
It's not like this doesn't happen. Probably more often than a woman staging a John Darwin disappearance and leaving 2 little girls behind.