What is the ruling on the feelings a committed girl has towards a committed young man, and what is the ruling on her refusing suitors in order to await his proposal?

You must be careful not to establish an illicit relationship with this young man. You should perform Istikhara (prayer for guidance) and consult trustworthy family members. Your feelings towards the young man are permissible, provided they do not lead to anything forbidden. You should not reject suitors merely based on an unconfirmed future event, for the Prophet, peace be upon him, said: "If there comes to you one whose religion and character you are pleased with, then marry him." You can consult your brother to find a solution to the problem. You should convince your father not to force you to marry someone you are not pleased with, and that you have the right to make the final decision.