I have massive sympathy for this poor woman and her family but it IS obviously a very complex case and "starved to death due to benefits being stopped" doesn't actually summarise the facts accurately.
If she was paying for a coffee and sandwich in a cafe then she had enough money to have eaten 3 square meals - if she'd been able to shop and cook, which she wasn't.
It really sounds like an unusually complex case - she had savings to buy a cottage, she'd run off repeatedly to places like Siberia and Israel, all of which cost money to get to! And she changed her phone constantly to avoid being bugged...
It basically sounds like she needed residential care, except that she didn't want it and would have been a constant flight risk.
Some people are very hard to help. I wish the NHS and SS had had the resources to do a better job of helping this woman to heal, I wish she could have lived a happy life. But I don't think she starved to death because her benefits were stopped.