What should a man do who is married to a woman he does not love, and married her against his will, and has abandoned her for four months and cannot approach her, and wishes to marry someone he loves?

The Shariah commands good companionship with one's wife. If it is impossible to maintain the marriage amicably, then divorce should be done kindly. Divorce is permissible. Abandoning one's wife for a long period merely because of a lack of love is clear oppression that requires repentance, especially if the husband neglects her other rights. It is permissible to keep the wife in one's bond and marry another, provided there is justice between them.