All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
Sharia enjoins consorting with one`s wife in kindness and enabling her to perform religious obligations. As for how long a husband is allowed to be apart from wife, Sharia hasn`t specified a certain number of days. Rather, this is governed by mutual agreement of the spouses in question since Almighty Allah Says {What means}: "But consort with them in kindness, for if ye hate them it may happen that ye hate a thing wherein Allah hath placed much good." {An-Nisaa`, 19}. As for the period of husband`s absence known to people, it refers to the policy placed by Omar Bin Al-Khattab (May Allah be pleased with him). Omar asked his daughter Hafsa: "What is the longest period a woman can bear being apart from her husband?" she said: "Six or four months." Then, he said: "I will not keep a soldier apart from his wife for longer than this." {Related by Al-Baihaqhi in Al-Sunan Al-Kubra, vol.9/ pp.29}.
In conclusion, We (Iftaa` Department) advise you (Asker) not to be apart from your wife and children for a long time and not to get so occupied with making a living at the expense of providing them with sufficient care. And Allah The Almighty Knows Best.