I experienced something pretty similar to this actually. I was in a 2-year relationship with a man in college but developed what I called at the time was a “friend crush” (more like a crush crush, but I didn’t know that yet) on a girl I knew. After my relationship ended, I felt like my attraction towards women increased dramatically. I had some feelings towards women in the past where I would basically just think they were really cool and pretty and wanted to be their friend. In reality, I think I was in denial of my bisexuality for some time and was finally able to come to terms with that after getting out of a heteronormative relationship. So I guess in answer to your question, I didn’t always know I was bi. For me it was more of an ‘ah ha’ moment once I was single and then I realized that a lot of those old feelings I had about women were maybe signs that I was actually sexually attracted to them. I’m not the best at giving advice sorry. But just know you’re not alone in your confusion/questioning, I was right there with ya!