In the article it is stated that he lost a total of £40k pounds of which £10k came from borrowing from friends, family and banks, the rest came from a property that he had sold, so fortunately for him he's not so heavily indebted and even if he has an average job he should be able to bounce back as long as he doesn't make another mistake, however losing so much money in one single night even for a reasonably wealthy person is is still incredibly painful.
This may sound harsh, but sometimes heavy financial losses are necessary to wean off gambling addicts from this habit. Hopefully he has learnt the lesson, and will never again involve himself with such behavior. And as you mentioned, it is not a life-threatening amount. The article also states that he has managed to kick the habit, after getting himself treated Cardiff-based at the Footsteps to Recovery institution. So eventually, this loss did something good to him. If he hasn't lost this amount, would he agree to the treatment?
At least there will always be good things after suffering and I think that treatment only happened because he had a big loss. That is, if he does not suffer a major defeat then it is unlikely that treatment will be possible, because the treatment he is doing is only for a recovery, perhaps because he is not ready for the defeat. Well, this incident can at least give a lesson to many people as well and not only for himself, having a lot of money doesn't mean we can spend it quickly because in gambling we have to be aware of the time to stop even though we still have money in our pockets.