The core business of banks is trading money-right-now for future-money and vice versa.
So if you have the type of financial problems where you need money-right-now but have some good future-money to offer in exchange, they'll be glad to help you make a deal (and vice versa for investments), and you should absolutely talk with your bank about such problems.
However, if you have the type of financial problems where both money-right-now and future-money are lacking, then yes, no bank is going to be helpful there.
So I did that and the way HSBC helped me was to immediately cancel all my cards so I was left high and dry. Since my problems had only just begun I realised my credit record was still good and opened an account with Barclays the next day who were more than happy to issue me cards and a line of credit.
The moral of this story is that if you have financial problems do not tell your bank.