Retire now, OP!
For those saying "oh, but you should have financially planned for the disparity in your ages" and "he's done his time, you'll just have to carry on until 60 like him, that's only fair" etc etc.....that's just nonsense.
On that basis then the DH should also have financially planned for all the extra costs he'll personally have when he's, say 75 and OP is 65, right?
Need a carer whilst you're recovering from that new hip when you turn 72, DH? Sorry, you'll just have to sort out and finance a care package as (as a 62 year old youngster 😜) will be off on my girls' holiday (you know, like the ones you had between 60-65 years of age), only fair, yeah?
Oh and there won't be many foreign holidays for us as a couple DH as now you're over 70 your travel insurance premium will be prohibitive (for you, not me!)
and so on and so on....
The point is that when you marry someone you become a couple and a team and you want the best for each other. So of course OP will look after DH when he's very old even though (in all likelihood) he won't be doing the same for her.
OP, you've financially supported your husband for the last 5 years and he's (deservedly) enjoyed his retirement but now he has his private pension and the means to support you both (even with a bit of belt tightening) he should be very happy to do so and release you from a job that you are simply not enjoying.
Also, his state pension should kick in at 66 (I think!) - that'll help too surely?