Me and my big mouth

I've always had a big mouth. When I was about five years old, we had a visiting preacher over to our house for lunch. When he asked my parents how they met, I said, "They met in a bar."
My mom audibly gasped and said, "We did NOT. We met in college," but the damage was done.
My parents did not meet in a bar. I said this because the lady who took care of me watched a lot of soap operas, and therefore, so did I, and even though I knew it wasn't true, I said it just to see what would happen. In retrospect, it's one of those funny stories from my childhood that my parents find endearing now, but, trust me, at the time, my mother was not amused.
This is perhaps the first instance I can remember of my mouth bordering on getting me into trouble.
I was considering all the different times my mouth has gotten out of control recently when I challenged someone to a game of Trivial Pursuit, trash talked about how badly I would beat them and then was pretty soundly defeated, therefore having to just silently accept it. These things happen, but it seems like they happen a little more often to me because I never know when to shut up.
The trashiest incident I've ever been involved was pretty much spurred on because I should've just shut up.
A really scary large girl that is probably the only person on this planet I can say that I truly hate was looking to start a "rumble" or something with me in a bar. She came up to me after I had seen her once already and made a pretty big show of just wanting to avoid her. The interaction went something like this:
Her: "You don't have to be that way, Emily."
Me: "What way am I being?"
Her: "Well, anyway, I just wanted to thank you for....(something that I don't want to go into here, but it involved a friend of mine who is no longer with us that I blame her for)"
Me: "You know what? I don't like you, you don't like me. You can go over there, and I can stay here, and we don't have to talk, and that's fine. Not a big deal; we're just not friends, and that's fine. And I don't want or need your gratitude for anything. Okay?"
This angered her.
Her: "Bitch, I can kill you."
Here's where I ran into trouble.
Me: "Ummm..yeah. Aren't you on probation or parole or something. See, I'm not white trash, so I don't have a criminal record. So, if you think you need to do something, I think the one of us with no criminal record will pretty much come out on top there."
I never saw her fist coming, but, boy, did I feel it.
Now, I won't go into the ensuing hullabaloo that followed this, because the actual incident is the example of my big mouth. I knew what a psycho she was, but I refused to have her intimidate me or have the last word, just because I can't. And trust me when I say, she could have reduced me to a fine powder had she wanted to.
I also told a group of friends when I was about 10 that I had spit up on Elvis Presley when I was a baby. My dad was from Memphis and had actually met him, but since he died exactly a week after I was born, that would've been fairly impossible.
Nonetheless, I had to retract the story soon after parents of friends came to believe that my dad had been drinking buddies with the King of Rock 'n' Roll and actually asked him about it.
Even the aforementioned broken ankle incident was predicated on my having to have the last word to one of my friends still in the bar and not paying any attention to the handicapped ramp that I so gracefully tripped over.
I don't know; I'm not going to apologize or make excuses for being a "mouthy broad," because I don't know any other way to be, and I wouldn't like myself if I suddenly became meek.
However, there may be a delicate balance to be struck between speaking one's mind appropriately and doing what I do that has given me a swollen cheek, a broken ankle and a stern lecture from my mother about how soap operas are not real.