All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
You are not obliged to keep your promise to marry that young man; rather, you should not marry him since he is not pleasing in his religion and moral conduct.
We ask Allaah to keep you firm on the right path and guide you to the best of your affairs and bless you with a pious husband who would help you in obeying Allaah and with whom you would be happy in this life and the Hereafter.
Allaah Knows best.