I agree with QuietMind. It doesn't sound like you have anything to gain from telling your mom. I'm sorry it's not a different situation for you. Also, the other thing is that although she's your mom, and although she's helping you out with tuition, you don't owe her anything. It's your life and you need to do what you need to do. You're never under obligation to disclose it to anyone for any reason, although there are all kinds of reasons people would disclose their gender based on their needs and preferences. I think that as you get further along on your journey you'll be better equipped to deal with a lot of it. For now, I think it's important to keep yourself safe while you're navigating the early stages of transition.