What is the ruling on masturbation ("hand-zina") due to being away from one's wife, given the mother's objection to the wife's return, and the work circumstances not allowing it?

We have previously explained the prohibition of masturbation and that by sincerity and following the directives, one can protect oneself. We advise you to fear Allah and be patient, and to seek a way to be with your family. If you wish to bring them over, try to convince your mother. If she is not convinced, there is no blame upon you, and it is not considered disobedience, because you seek to protect your chastity. Exert effort to appease her if she becomes angry. You must cling to Allah and ask Him for success and ease in your affairs, instead of wishing for death. This is based on the Prophet, peace and blessings be upon him, who said: "None of you should wish for death because of a calamity that has befallen him. If he must do so, then let him say: 'O Allah, keep me alive so long as life is good for me, and cause me to die if death is good for me.'"