Patrick, you story speaks volumes about the attitude of the banks - many thanks for sharing it. Unfortunately, of course, it's not a "story" but real-life that could have ended very differently. If there was no negative equity for example, you could well be homeless now. Can you say which bank it is?
MARP is completely one sided: the bank can effectively declare it over with no right of appeal other than to the same bank. You can be declared as non co-operating with potentially drastic consequences, yet there's no sanction for banks that won't co-operate.
Well done on getting back on track: I find it appalling you haven't been given the opportunity to square things with the bank to end the stress of the uncertainty.