It's not just a phase...

Before I turned 17 I told my mother I was bisexual (I'm pansexual but at the time I didn't realize and i thought I was just bi even though I knew it didn't really fit exactly to what I felt, it was the closest thing to it that i knew of) and she told me "it's just a phase" and then informed me that i was to marry a man and only date guys and if I married a woman she wouldn't come to the wedding. Now I'm afraid to bring it up again, and if the topic comes up she will look at me in a way and say "well you're over that 'curiosity' thing now so that's good" and im actually kind of scared she won't accept that i am pansexual for real and i prefer girls over guys. Sorry for the long post, it's just something I've had to express for a long time.