Is it possible to stop yourself from being bi?

you cant stop cuz

you kissed a girl and you liked it the taste of her cherry chapstick

Even if you want to, I'm afraid not. Sexuality is determined from birth and cannot be changed no matter what kind of therapy you go through. There are some people who claim that they can "heal" you and make you straight, but no such people tend to try to scare people into acting straight. These people end up leaving this "therapy" scared and confused, and not "healed" at all. The truth is, there is nothing wrong with you if you are LGBT (Lesbian, Gay, Bisexual, or Transexual) and people saying that they can make you straight might as well say that they can change your DNA. The best thing to do is to embrace your sexuality and just try to ignore the criticism and predjuice that you get. Just do what your gut tells you to!