What is the ruling on my remaining with my husband in the same house, despite his abandoning me in bed, knowing that he squandered my money that I earned from my work and established a relationship with another woman? And am I, by doing so, committing a sin? And what is the solution?

The way to resolve disputes is through understanding or judicial recourse. The wife must remain in the marital home, obey her husband in what is good, and enable him to exercise his rights. The husband, in turn, must treat her kindly and provide for her financially. If the husband falls short, the wife has the right to resort to the judiciary or seek a divorce. If the wife agrees to remain with a husband who does not provide for her, she has the right to refuse intimacy. Accusing a Muslim of an illicit relationship without proof is a serious matter. If the wife ascertains her husband's illicit relationship, she must advise him and warn him. If he repents, she should treat him well; if he insists, it is better for her to separate from him through divorce or khul'.