Every language has a grammar, a set of rules that govern usage and meaning, and literary language is no different. It’s all more or less arbitrary of course, just like language itself.
I had had a feeling of freedom because of the sudden change in my life. By comparison to what had come before, I felt immensely free. But then, once I became used to that freedom, even small tasks became more difficult. I placed constraints on myself, and filled the hours of the day. Or perhaps it was even more complicated than that. Sometimes I did exactly what I wanted to do all day—I lay on the sofa and read a book, or I typed up an old diary—and then the most terrifying sort of despair would descend on me: the very freedom I was enjoying seemed to say that what I did in my day was arbitrary, and that therefore my whole life and how I spent it was arbitrary.