why may i be asexual

i want to love but i fear sex.  i fear sex because of the trauma from the sexual child abuse.  and now into my adulthood i fell out of practice with having a sexual relationship with women.  i am attracted to women.  i'm like a school-boy when i see a woman i am attracted to.  i freeze-up when a woman show any interest in me.  when i am alone with a woman i get nervous.  i feel safer with women when they have a boyfriend.  i like to take them out and be a gentleman.  but always the lady will go back and tell their boyfriend how nice i was and what a good time we had.  their boyfriend will get jealous and the relation i have with the woman will end.   i realize my friends were children and people much older than me: parent and grandparent figures.  i'm safer in around thse age groups.  i never cared to be around people my age.   when i am around gay males who's conversation is about sex, i'm turned off.  i want to be friends with everyone - i know that is not realistic.  i try to befriend people i know are gay.  but sometimes i feel like they are trying to make me gay.  this guy i met suggested i dress up like a woman for halloween and asked if i was going to a gay parade.  when i said no he commented that i should.  i know he meant no harm, but it just feels funny.  i wonder or worry if i am sending out a signal.  i'm questioning myself.  i feel confused.  i want to find away of letting this guy know that he made me feel uncomfortable without offending him. i think people think i am weak because i come across too nice.  i'm quiet.  i'm to myself.  i think they think i am hiding something.  i dress nice. all that stuff they the are glues of being gay.  it's ignorance.  i'm getting upset.  i'm going top close it out here.