Judging from your description, your grandmother may have neglected or overindulged your education and discipline in some ways, which has led to some problems for you now. However, this does not mean that you are fully responsible or that your grandmother has no responsibility at all. At the same time, your aunt may be more inclined to believe your grandmother's explanations and excuses, which is understandable.
Emotional communication and rational thinking are very important in dealing with this relationship. First of all, you need to try to objectively evaluate your behavior and the changes you need to make, and admit your mistakes or shortcomings; Secondly, you can communicate with your grandmother or aunt properly, express your views and needs, listen to each other's ideas and suggestions, and seek solutions; Finally, if you can't get satisfactory results through communication, you can consider consulting professional psychologists or family relationship therapists for advice and suggestions.
In short, family relationships are often complex and sensitive, and we need to respect each other's feelings and positions when dealing with them, and always keep an open mind and constructive solutions.