What should I do about my husband's abandonment of me—including his conjugal rights—after he married another woman without my knowledge?

A man's marriage to a second wife is permissible if he is able to be just. If he does not share the bed with you without a valid excuse, then he is an oppressor, leaning towards his other wife. He falls under the warning of the Prophet, peace and blessings be upon him: "Whoever has two wives and inclines to one of them more than the other, will come on the Day of Resurrection with one of his sides drooping."

Therefore, he must fear Allah and be just between his two wives in terms of overnight stays, financial support, and housing. The wife is advised to handle the matter with wisdom and gentleness. If he does not respond, assistance can be sought from someone who has influence over him to remind him of his obligations.