Did I disappoint you or let you down?

To start off, yes, the title is a quote from a James Blunt song.

Here's a little background. My younger sister has told me a few times that my outgoing personality and the fact that everyone knows that I'm bisexual (or they think I'm a lesbian) negatively affects her life. Apparently because people also know that my dad is gay, they think that she is a lesbian and we are all one big, happy, gay family. Also, people often talk to me about how much of a slut my sister is and how short her shorts are and such. It really bothers me that people think she's a slut.

Last night I was at a post band camp pool party after our first performance. I was talking to a good friend and I mentioned one of my sisters. My friend asked "You have a sister?!"
I replied "Yes, two." I said "My older sister is a year younger than yours, but you probably wouldn't know her because she moved in with my dad after middle school, but you might know my younger sister, Jess." My friend said he didn't recognize her name, so I told him who a few of her friends are. He asked if she was the skinny one with the long, blonde hair. I told him that yes, that is her.
My friend then said "So you and your sister are both gay?"
I said "No, she's not. Why would you think that?"
He said "I always thought that she was a lesbian."

Tonight at dinner with my sister and my mother, I told my sister what happened. I explained that it's not all my fault that people think she's a lesbian. Someone that had no idea we were even related thought she was a lesbian. We got into a big discussion that included my mom about how Jess wishes I would be less gay. I told her that I wish she would dress and act a little less slutty. I continued by telling her that no matter what situation you are in, people are going to assume things that aren't true and no matter what you do, there will be people that don't like you. We continued with our conversation for a little while.

Soon, my mother was just as much a part of the conversation as we were. She confessed that she too was uncomfortable with me flaunting my gayness. She gave the example of how she was not comfortable when I've had girlfriends in the past and I've kissed them goodbye. I asked her if it would be any different if it was a heterosexual relationship. She said that no, it wouldn't be any different. I then basically told her that either that's a steaming pile of bull shit or she's a hypocrite. Whenever she's in a relationship, even if we're running late, she'll take five extra minutes to completely get it on to "say goodbye" right in front of my face. Of course, she has to make up for the hour and a half that they're going to be apart and will not be able to go at it.

I just wish my mother could be a little more understanding. My father is proud of me for not being afraid to show who I really am. I don't really know what my mother wants from me. If I were normal, she'd be trying to get me to come out of my shell. It's me who has to go through the torture of other kids. If I'm willing to go through that, why can't she deal?