"I think maybe when you live with someone who is really very ill for a long time, it somehow gives you more of a greedy appetite for life and maybe, yes, you are less measured in your behaviour than you would otherwise be"

Nigella Lawson's quote suggests that coping with somebody who is really ill for a long period of time can have a profound impact on a person's outlook on life. It can provide a "greedy hunger for life" and make them less determined in their behaviour. This could be because they have actually seen the fragility of life and wish to take advantage of it while they can. It could also be because they have been through a hard experience and wish to take pleasure in life more than they did before. Whatever the factor, it is clear that living with somebody who is very ill can have an enduring influence on a person's mindset and behaviour.