Will I be sinful for abandoning 'Umrah and telling my mother "I hate it" after an argument that occurred between us as a result of her going to perform 'Umrah alone and her cursing me?

You have committed a great sin by arguing with your mother and telling her that you hate her. This is an act of disobedience (ʿUqūq), which is considered one of the greatest major sins (Kabāʾir). You must immediately repent to Allah, seek your mother's satisfaction, ask for her forgiveness, and continue to be dutiful to her throughout both your lives. As for your return without performing 'Umrah (definition) after entering into Iḥrām, this is a mistake. You must return to complete the 'Umrah and refrain from the prohibitions of Iḥrām until you complete it.