How do I deal with my ill-tempered mother, who speaks in a threatening and menacing way, especially since I am abroad and she knows my difficult circumstances?

You have done well in trying to please your mother and using a good approach. We advise you to frequently supplicate for her well-being, in compliance with the words of Allah Almighty: "And lower to them the wing of humility out of mercy and say, 'My Lord, have mercy upon them as they brought me up when I was small.'" (17:24). It is obligatory for you to be careful not to commit any offense towards her, even if she offends you, for her right to your dutifulness and good treatment does not cease. Emphasize the importance of supplicating for her guidance and righteousness, and be keen to identify the cause of her anger and address it, avoiding everything that provokes her resentment. You can seek help from virtuous relatives or others to assist you.