Is my wife still under my marital bond, given the abundance of thoughts and intrusive whispers of divorce that plague me without uttering them, and am I sinful for that?

All the mentioned whispers and doubts do not bring about divorce or affect the marital bond. Therefore, the questioner should take his wife back and treat her kindly, and completely disregard these whispers. He should also consult a psychiatrist and seek help from Allah, and supplicate frequently to ward them off.