How can a married woman act regarding her marriage, which she describes as unhappy, and her discovery of her husband's betrayal, and her falling in love with another person while feeling guilty?

You must rid yourself of any feelings of love for the other person and ignore them completely. It is forbidden for you to do anything that would increase this love.

Be frank with your husband about the problem you are facing regarding his turning away from you and his attachment to someone else. He should either keep you honorably or release you kindly, as Allah Almighty commanded.

You must do what makes him love you and remove what causes discord. If you fulfill his rights and he does not fulfill yours, and you are unable to be patient, then you have the right to request a kind release, unless you have children together. In that case, we advise you to be patient and stay with him, and to seek refuge in Allah to rectify his situation, as your separation in the presence of children entails greater harms.