Bottom line, 2 out of every 3 transsexuals commits suicide before age 30, so your mom did OK with you. She has done her job, she made sure that you survived until you were old enough to make your own decisions. You have honored her for 47 years, by NOT doing what you have wanted to do most of your life. If you are only a cross-dresser, and have no desire to transition, then your mother doesn't need to know more than she already does. You can dress like a man when you are with her, and accept her the way she is, and the way she isn't. If she doesn't like that you have a boyfriend, then don't invite her to your home. Meet her at restaurants, or go to her house alone, but not too often. You may want to consider moving to another state. If you can make more money, live in a more tolerant state, get legally married, and have some true happiness, and your mother doesn't want you to have that, then it's time to go. You'll have the phone.
It's sad that the Christian church has continued to stress mistranslated passages in a less important section of the bible out of context, as if they were the cornerstones of the Christian Faith. It's sadder still, that the church insists on driving that wedge between parents and children, and between Fundamentalist Christians who believe that all gays, transvestites, and transsexuals should be killed, and the world that is more accepting, loving, and tolerant. Ironically, the persecution of gays and transsexuals didn't get really hot until the expansion of the Muslim empires, under Genghis Khan, Kubla Khan, and Suluman - who expanded the muslim empire from Romania to the eastern shores of China and Indonesia.
Even then, the issue was with young boys who tried to pretend to be women in order to be spared the fate of ALL males, from infants to adults, which was to be put to death on sight. Young attractive women were the only ones spared. If a boy dressed as a woman, and acted seductive, and eventually submitted to a man, he might be spared, at least long enough to escape.
In Africa, younger teenage boys were castrated and worked as servants and guards in the harems.