Here’s a revised version of your message in more proper English:
"Ma, you are the only person in both of our families I can truly confide in. It hurts me to bring this up, but I need to express what's been on my mind. I’ve noticed that Tlholo’s mother and Bravo’s mother behave in very similar ways. You know what I mean; remember how Bravo's mother never had any kindness for Khutso, just like Tlhologelo’s mother treats my younger brother and me.
I recall the time when Amu was living with us. She used to call occasionally, but that has stopped since Amu is no longer with us and Mama has passed away. I want to clarify that I’m not suggesting she should call us. What truly pains me is that after I failed my matric, I never told anyone in my family—I only confided in Tlholo because she asked me. She then informed her mother, who called Mogau and said, 'I’m not surprised that Thato failed her matric; during her mom’s funeral, her friends were only giving her papers.' It hurts me deeply to think that she would celebrate my failure like that."
Feel free to modify any part of it further to better reflect your feelings or thoughts.