So is your car on finance?
You're asking two things here really.
-1 Can you manage on TWO state pensions (that's different to just one.)
-2 Can you manage alone, if he dies first, on ONE state pension.
The answer to 1) is yes, but you'll have to be careful It's worth looking online at this because there is guidance. The upshot of it is that £25K pa gives a basic - ish standard of living but not much wriggle room for overseas holiday, new cars, or a lavish lifestyle.
The answer to 2) is 'probably not'. This is because most of your fixed costs will be as much as or slightly less than for a 2 person household (not half.) Your bills already come to more than the state pension. So you'd be dipping into savings just to get by, or would need to downsize.
You need to plan for your older age, from your late 70s into your mid 80s or older.
If you have savings, are they 'inflation proofed'? Are they in accounts keeping up with inflation so that in 20 years they will not be worth a lot less?
How much savings are there? If you had to live from 75 to 90, on a state pension, how long would those savings last if you had to take £10Kpa out of them?