The life of an Indo-Aryan individual was divided into 4 stages of 25 years each:
Brahmacharya is the stage of education in Gurukul under a guru. (0-25 years)
In the Grihastha stage, the person would marry and bear children. (25-50 years)
During the Vanaprastha stage, a man would give up his worldly life and would retreat into the forest to meditate. (50-75 years). In this stage, the individual could be accompanied by his wife.
During the Sanyasa stage, the person would become an ascetic. Basically, complete renunciation from the world. (75-100 years). In this stage, even the wife was not allowed to accompany the individual.