If you're asking can you not be gay? No. Ex gay therapy does not work and is a major waste of money and human destruction.
Its on the LGSBT section of the forum under a thread called "Gregs Gay Support / Healing" or something. Look for a movie called Prayers For Bobby and show it to your mommy/daddy and I guarantee it will probably make them think twice. Show them The Bible Tells Me So next if they're still trying.
Ill get the link for ya here it is... Prayers for Bobby: http://emptyclosets.com/forum/showpost.php?p=445794&postcount=47
They can change your attitude towards your sexuality, but they can't change your sexuality. If they keep telling you that you're wrong, that you're not gay, that you'll "see the light" eventually, you might start feeling like you don't want to be gay, but it won't change who you're attracted to.
Parents, friends and family can INFLUENCE the way we think but only if you let them. Your thoughts and feelings are yours and yours alone, if you feel at ease with what you are feeling and thinking then you can listen to what people have to say but you don't HAVE to agree or change what you feel inside. Everyone is allowed their own opinion that goes as much for your parents as it does for you. You do NOT have to agree with the point of view of the people around you.
As the others said. They can influence the way you think about it by heaping shame and guilt (or, in other cases acceptance and love) upon you. But they can't change the way you feel. If you are a hypothetical 100% gay man, the way to truly feeling attraced to a woman is forever closed to you. Then again, it is a spectrum. I've never truly fallen in love with a girl, but it is conceivable that there is one rare specimen out there that I could love and feel attracted to. There's not a whole lot my parents can do about that, though.