I think my best friend is starting to have feelings for me

I've had this friend of mine for 3 years, we met at one of my old jobs. We're both girls, she was 19, and I was 25 when I met her. I have had romantic feelings for her since we first met, and asked her out after almost a year (1st year of knowing her), although she had turned me down. She was my best friend and I was scared of losing her if I admitted that to her, but she told me she couldn't because she only likes boys. For years now she's been telling me sex stories about her and guys she hooks up with. When I left my last job I nearly had her blocked for almost a year (2nd year of knowing her), I was trying to repress my feelings for her since I was already in a relationship, and she had moved to New York (After about a year of us working together). For one she CONSTANTLY claims she's straight but will tell me all these stories, it's so confusing.

(3rd year) About two months ago we came in contact again after she called me from a private number telling me how she missed me and has been trying to talk to me for months. We started talking again, she came down to Florida this past Friday and we ended up getting drunk together at a bar, she kept joking about trying a 3sum with me, I kept touching her and telling her how I want to do everything with her and go on all my vacations with her, then I ended up giving her hundreds of dollars (idk wtf is wrong with me) Then this weekend she flew back to NYC and Hooked up with two different guys (one in FL before she left), her crazy slutty ass.. and told me about it and how she wishes I was there. I'm going crazy, I have to go to the car for hours because she tells me these stories while I'm at work. Then when I sneak back into work I can't even concentrate, and she will tell me she loves me and I swear I think she knows I get a thrill out of it. I don't know what to do, I'm Bi but I've never slept with a girl (only kissed) and I don't think she has either, she always says she's straight but i'm so confused.