Two adults, two cats. One 3 bottle box of wine per week then usual food for the week. Some weeks are more expensive than others if we need dishwasher stuff or cat food, for example, but a standard week is around £100 - £120.
Most expensive shop recently was £152 but included two boxes of wine as my parents were visiting (£40) and cat food (£15).
I used to spend less with Sainsburys online, but their fruit and veg was awful and we spent every weekend traipsing round other shops to top up. We used to have a lot of wastage, so the better quality stuff from Ocado, even though it's more expensive, and getting it all on one shopping trip has, surprisingly, made it cheaper overall.
Worth noting though that M&S stuff from Ocado is more expensive than buying it in the shop. A beef joint that sells for £9 in M&S is £10.50 on Ocado. I have switched a lot of stuff to the Ocado brand and a lot of it is much nicer. For example, their Turf & Clover beef roasting joint (700g for £7.50) is much nicer than the M&S Aberdeen Angus beef joint (450g for £10.50). As it's just 2 of us, I buy the T&C one, cut it in half and £7.50 gets us 2 roast dinners instead of £10.50 for one!