You're begging the question by assuming that asexuality is an orientation instead of a lack of any sex drive. By the dictionary definition this is just wrong (and it's semantically equivalent to arguing that atheism is a religion).
We get it that you want to redefine "asexual" to mean something like "not being attracted to anything, but still having a sex drive and masturbating, and I want it to count as a sexual orientation so we can piggyback on the gains made by the equal rights for gay/bi/trans movement". However that's not what the word means, and it's a poor fit, so I'm still wondering why you want to appropriate "asexual" for this purpose when there's already a group of people using it.