Can't see myself as gay [Discussion]

I'm a girl and I started dating the most beautiful, loving, caring and funny woman i've ever met when i was 14. I'm 18 now, and still in a relationship with her. She makes me so happy and she's just amazing.

The problem is that i feel like i'm not myself. Not because of her, i love her and when i'm with her i'm basically with myself. I feel this way bc whenever i realize that i'm dating a woman or having sex with a woman, i get something like imposter syndrome about the fact that i don't think of myself as a gay person. I "look" straight, i have only straight friends, i never imagined myself with a woman until i met her. I'm very confused about who i am because i feel like i had this image of myself as a straight/boy crazy girl all my life but i feel like i am someone else now and it feels so difficult to understand who i am.

Any advice?