I don't think the two of you actually disagree, I think you're just using the term 'life' differently. You're making the point that there are parts of life that are manmade and subject to change, like the economy which can and should be changed to help people. Meanwhile they used the phrase 'life isn't fair' in what they're saying is a descriptive rather than a prescriptive sense. They don't think of it as a thought terminating cliche and they don't oppose reform, they just see it as an accurate and realistic outlook for the time being.