And that's from someone that would almost certainly be in for some business if you didn't
Seriously though, I know how you feel as I had an accident last year, luckily only the drivers side of my car was wiped out, my Zed was on 90k+ so I started looking around at replacements thinking it would be written off but the Insurance covered the repairs as they were confident the other party would be paying, although it still isn't sorted...
It would have been heartbreaking to loose the car as like you it has given me very few problems given the mileage on it, but at the end of the day the damage to yours is so great that it really wouldn't be worth salvaging even with all the nostalgia attached, you would be spending more than it would be worth and once finished it would be devalued even more because of the damage / repairs.
£6.5k is a decent figure I reckon given the mileage....