Everyone has his own personality and lifestyle, and some people may prefer to act alone and enjoy the time and space alone. This doesn't mean that they don't like socializing or don't want to associate with others, but they are more inclined to their own lifestyle and rhythm.

University life is often very busy, and it takes a lot of time and energy to study and finish homework. A person chooses to be alone in order to be able to study more intently. Too normal.