Central banks do help banks by 1) accepting to move funds deposited with them from one bank to another, and 2) by advancing funds to them.
When setting the interest rates up or down it is the economy and not the banks that they have in mind. This is ELEMENTARY.
"The academic J.W. Mason did an interesting piece of analysis in "Interest Rates and Bank Spreads." He was responding to an internet debate, which I am not directly addressing. In Mason's article, he crunches the published average bank interest rate charges (both lending and borrowing), and shows that they are consistent with a relatively steady spread regardless of the level of interest rates"
I presume that at 43 it would have been more appropriate to ask for a 20-year home loan, which, of course would require, a larger initial deposit or perhaps a guarantor.