Have you contacted Victim Support? They might be able to help you after the burglary.
Has the bank explained why they won't help you with the hacking (or was it a scam? It's not very clear). I thought that they would cover hacking, as they should be able to prevent this, but scams are a different matter, as unfortunately the account holder has often instructed the bank to act. If it was indeed a hack, it might be worth taking things further if they absolutely refuse to help.
As has been suggested, you might be able to come to an arrangement to pay back HMRC in instalments - it's worth a try.
The UK state pension is a disgrace. People who pay NI contributions for decades often end up with less than those who don't work at all, and the system works against those on low pay, who can earn so little that they don't pay the relevant contributions. In that case, though, you should qualify for pension credit, so do make a claim if you can.
Your GP may be comfortably off, but that doesn't mean that she has no idea about the lives of patients who are less so. Most GPs see a patients in a wide range of circumstances, so don't be put off seeing her.
I'm sorry you are in this situation. Can you draw up a repayment plan, so that you can see when your debts are likely to be paid off? As you approach the end date it might cheer you up to see that it is in sight, and you can plan a treat for when you get there.