I did it. I finally came out to my parents today about 45 minutes ago. I was the one crying and not them. My mom said, "I guess there's a reason you're 5'10"." She said that she will help me and be supportive me. She also said "I don't care if you're my son or my daughter. I love you for you."
I was so scared and I admitted this. I was crying for a good part of it, but everyone was supportive. My dad might be harder to win over, but that's fine.
I haven't expected them to call me by a preferred name [my mom wants to name me] nor have I asked for them to use pronouns yet, but that's fine.
Just knowing my mom said she would whallop anyone who makes fun of me or is mean to me makes me happy. ^_^