A lot of people appear to dislike
Les Mandarins, which I think is a pretty excellent novel, so let me try and explain what I think is good about it. To me, it's basically about what happens to people (particularly to women) when they realize that they are no longer young. This has several consequences. To start off with, not being young means that you're no longer as physically attractive as you were. Of course, you can go into denial, and say that as long as you eat healthily, exercise, and think positive thoughts, you're going to stay young and tasty for ever. But let's be realistic.
The rest of this review is in my book If Research Were Romance and Other Implausible Conjectures