Discussion: I am a young lesbian. I have very bizarre sexual fantasies. Is it possible that my fantasies are related to my sexual orientation?

Sexual fantasies are associated with sexual behavior, expressing how everyone experiences sex. (See definition).
Sexual identity and sexual orientation are necessarily related to each other, but sexual behavior is a separate phenomenon (derived from different mechanisms). Sexual fantasies are not detached from sexual identity and sexual orientation but are not integral to sexual orientation.

Sexual identity, sexual orientation, and asexual behavior. (Simplified definitions)
Sexual identity - refers to the sex to which we feel emotionally-energetically connected; most often, it is our biological sex. Occasionally, there is a conflict between the biological sex (with which we are born) and the sex we feel connected to.
Sexual orientation usually answers the question of which sex we are attracted to. (It can be Opposite sex, Same as ours, both sexes, or neither.)
Sexual behavior - How humans experience and express their sexuality. (Sexual behavior - Wikipedia)