Your cars break much more often than mine do. I put over 90,000 miles on my last astra (added to the 20odd it had already done) with no more than annual oil changes, and I never had to call out the RAC once 
This one is coming up to 70,000 and is still running sweet 
Mine all have a lot more miles... ...although in the case of my current car, most of the issues have been down to moronic design decisions made by Ford and PSA.
I'd expect anything modernist to last to 100k even will only an annual oil change and brakes and tyres as a when required. It's the 100k to 250+k when you start to see the results of piss poor servicing. And diesels still heavily contaminate the oil with particulates (hence the oil goes black almost instantly) which is like running grit in your oil. Modern diesels also water the oil down with diesel as well, to varying extents.
Add to that, *nobody* makes an oil that in standard car sump sizes will not have mostly broken down in 7k...
But if you only keep to 100k, who cares, and when it's sold on, its not your problem

. You probably over service the car in that case...