They had debts that significantly exceeded their assets and with no sign of getting back to work that would allow them to repay the debts in a reasonable amount of time, it's often advisable to go bankrupt and start again from scratch.
The alternative being struggling for years treading water against interest and charges meaning that they pay all their income towards the debt but don't make progress towards paying them off.
There's many places where property prices dropped in 2007 and still haven't got back up to those levels (Northern Ireland and Aberdeen I believe, also anyone who's bought new build in areas that haven't seen huge house price inflation in last few years). So they don't have an appreciating asset to hold onto.
In this case it also looks like there's been an overspending issue with no contingency for loss of income etc. If he's good with money, either he's now more cautious, or it was his ex who was the spender in the relationship.
He's always going to have to declare that he has been bankrupt, but the effect on his life could be minimal. Some finance providers might refuse to take his business, but there's plenty who will, often with little or no extra cost due to his financial history, especially when it drops off his credit history (6 years from when he was declared bankrupt).