There is absolutely nothing wrong with being bi.

I am bi myself, it has not made me into a pervert, I am quite happily in a 3.5 year relationship with my partner (we just recently moved in together! ) My partner is also bi. No we don't cheat on each other, and neither of us are 'slutty' or 'can't choose between one sex or the other'.

Why do I have to say this? Because so many people don't get it, and buy into all kinds of ridiculous ideas about what people are like. When I came out to my mother, she thought I meant that I had to always be with both a guy and a girl at the same time!

Bottom line, being bi just means you have the potential to be attracted to guys or girls, in the same way that a straight or gay person only has the potential to be attracted to one or the other. You may have a preference of one over the other, you may not.

Don't let your brother's misconceptions about bi people influence you because that's all they are - misconceptions. I've had fulfilling relationships with both guys and girls - you can too. Ultimately, follow your own heart, wherever it may lead you. Good luck