Fall For A Straight Person

I have a friend that I made in my last year of university and we became really close during that period. As in, I would go over to her house almost everyday to the point that I would just be able to let myself in, and would stay the night regularly - we've basically seen each other naked. I've recently come to terms that I like her as more than a friend but with the way my personality is and how we treat each other as friends, she's never able to take my advances seriously. I've been told by many people that i'm very unserious so I can see why, but it's gotten to the a point where I think she's just playing with me. Shes aware that I like women, but I remember she once told me "used to be bi" and "that phase in the past now..." I dont really know how to feel about those statements as when we interact with each other in real life and via text, theres always a suggestive air about it - its borderline sexting but i know a lot of straight girls who act that way with their straight friends, heck I even do that sometimes! BUT SHE HAS TO KNOW THAT IM DEAD SERIOUS WHEN I TEXT HER SAYING SHIT LIKE "I WANT YOU SO BAD" LMAOOOO. But I also think she just likes the attention, she has a roster of men in her DMs saying the craziest, most down bad things to her - i'd hate to think that sees me as one of them. Shes told me that our relationship is different from the guys she talks to and posts on her private story, but I'm not sure if thats the case at all. It feels like everything we say to each other is purely just banter. I used to silently criticize others for falling for straight people, but now it's happening to me, it hate it so much but I cant stop myself.
I hope i'm not reading too much into her advances but I dont know if I should try being more straightforward. I really like being her friend, so is that all I should aim to be with her?