Hannah, for your £1,000 budget, 34 miles trip 3 times a week, 5,000 miles a year in all weather, not many bikes will make it. Mike63 does a similar mileage. He bought a Woosh Sirocco CD a couple of years ago, then changed it for a Kalkhoff Sahel Premium i360 last year then changed it recently and bought a Kalkhoff Tasman.
If you can afford a Kalkhoff, then go for it.
If not, the tried and tested bikes for this sort of mileage and budget are Woosh Krieger if you weigh less than 80kgs, Woosh Big Bear if you weigh more than 100kgs. There is also the new Woosh Karoo that will do that sort of mileage, but you need to be 5ft8 or taller.