Thanks for the advice so far.

I managed to get myself on the bike today and had a good ride. I am trying to vary things a bit.

I changed my normal route about a year ago to a quicker route. I did my old route this morning, which is nice in spring/summer as some of it goes over a park area. It has one very congested bit which is unpleasant but over relatively quickly.

I will then do my usual route on the way home because it's faster and the traffic isn't as bad as in the morning (there are often quite a lot of HGVs on the route in the mornings) and it also goes past the supermarket I like to use so I can stop for my shoppping.

I think having a break from time to time is ok anyway. I attend a book group once a month, so getting the tube for a few days to help me finish the book is useful and then gives me a break from cycling.