Is it permissible for me to marry another woman after I promised my wife, by the Book of Allah, that I would not marry anyone else, following the death of our daughter and my agreement under pressure from her family, knowing that I am not comfortable in my current marriage and wish to marry the one I love?

The promise your wife took from you not to marry another is an oath that must be fulfilled or atoned for, due to Allah’s saying: "And fulfill the covenant of Allah when you have covenanted, and do not break the oaths after their confirmation while you have made Allah, over you, a surety. Indeed, Allah knows what you do." It is incumbent to strive to fulfill the covenant with Allah, the Exalted, unless harm results from it, such as fearing falling into indecency.