Sanyasa means both attachment and detachment. It means both attachment to God and detachment from the world. The internal attachment to God is important, which is indirectly measured by the external detachment from the world. You are not eating the food since you are engaged deeply in your studies. Your absorption in your studies is indicated by your fast. But, you may fast even if your stomach is suffering with some problem. You may also fast due to absorption in reading a novel. Therefore, your fast cannot exactly specify your studies. The fast can indicate various reasons. Arjuna wanted to leave the battle due to blind love on his grandfather and not due to detachment from kingdom. Therefore, Krishna advised him to fight the battle because his mind was not attached to God resulting in detachment from kingdom. In these days, the detachment of several saints is due to several reasons and cannot be attributed to real absorption in God. There is nothing wrong in marrying a girl for the sake of association, which helps in several aspects. If your wife is also spiritual interested and if you are engaged in thinking about God with the help of discussions with your wife, such a married life is real sanyasa. In sanyasa also, you have to be in association with several devotees to discuss about God. If you are wearing saffron cloth to achieve money, fame etc., such a state is worse than the state of householder. If you are engaged in worldly affairs always through the discussions with your wife, you will be born again and again in this world only and this is the normal middle level. Therefore, turning your family into devotees is the first step in the spiritual path. If your wife and children become devotees to God and participate in spiritual debates with you, you will reach the goal of a true saint.
The main duty of a saint is to propagate the spiritual knowledge in this world and for this purpose sanyasa is taken. In olden days, the person has to travel by feet from one place to the other and therefore the family-life became inconvenient to take up such long tedious journey. Today there is no such need because you can travel to far places within very short time. You can convey your arguments through computer and receive the counter arguments from the other people through the same computer within no time. Such facilities made the propagation of knowledge very easy task and hence today there is no need of leaving the family for the sake of propagation of knowledge. Even from this angle also, you can be a saint in doing the duties of a saint while remaining with your family. You need not leave the family in physical sense. When God competes with your family to test your devotion, you can prove your real attachment to God and subsequent detachment from the family. Sanyasa means internal attachment to God and internal detachment from the world including your family, which can be proved externally in the time of test. Saktuprasta was a householder and passed the test of God. He reached the abode of God (Brahmaloka) along with his family and such fortune was not seen even in the case of several saints. All his family members were strong devotees to God and co-operated with him to succeed in the divine test. It is always better to become a householder and mould the family to the spiritual side. Then you will get the advantages from all sides. Doubting your ability to mould the family, if you avoid marriage, it is just like burning the house for the fear of rats. God Brahma told Narada that Krishna was the real sanyasin. Krishna was always fond of ladies and Narada was surprised about this statement. You can see the true color of Krishna, who watched the mutual assassination of all his family members without any interference. He was after Gopikas only to test the attachment to their families. Gopikas recognized Him as God and this point is revealed in their songs (Gopika Geetha) in Bhagavatam. Hence, God competed with their family bonds and those who failed in test complained to His mother with anger. Gopikas were sages in the previous life and all those lives were the study time of the academic year. The present life of Gopikas was just the time of three hour examination. Even in the past lives of sages, they were householders only and developed in association with their wives and children. In no life they were sanyasins leaving the family life. As sages their family members co-operated with them in spiritual development. But, during the time of examination, their family members opposed them because examination needs such environment. You can be tested only in the opposing circumstances.
You need not approach only a saint for the spiritual knowledge. Krishna gave Bhagavat Gita, which is the top most spiritual knowledge and Krishna was a householder only and not a saint. Shankara was a saint and wrote commentary on Gita told by a householder! Shankara avoided the family because there were no facilities in those days in taking long travels for the propagation of spiritual knowledge. In your old age, you can limit yourself to the association of your wife only, so that both of you can participate in spiritual discussions due to old age of both of you. If you stay with your children, you will be associated with their worldly problems. This state is called as Vanaprastha. Today, people are avoiding the children due to the probable quarrel between mother-in-law and daughter-in-law or lack of freedom with the son-in-law! The old couple stays separately and thinks always about the worldly problems only. If the old wife is not co-operating with you spiritually due to her worldly attachment, you can leave her with the children and live in association with true devotees and this is the state of sanyasa. This state can happen if your old wife, who was a spiritual friend, passes away before you. This is called as Krama Mukti, which is the gradual sequential order of the life. In the present time, there is no need of leaving the family in the beginning itself like Shankara. If you cannot change your family into spiritual path, you are not competent to change the society into spiritual side. In spite of your trails to change your family in to spiritual side and if you feel the hindrance of your family in your spiritual development, you can still lead the married life taking its advantages and spend more time in association with true devotees than in the house. Of course, in extreme case of serious hindrance from your family, you can think of sanyasa as an exceptional extreme step and generally this does not happen unless it is a divine test.