Mislead

I have a best friend that I have been friends with for 3 years. The first and second year of our friendship we began having more a sexual friendship but there were no strings attached. Now that it is the third year of our friendship the sexual aspect of it has gotten more intense. We stared in each others eyes and constantly tell each other how much we love each other. We had sex almost every night and I feel like I'm falling hard for her and I suspect she knows. The thing is she met a guy who she really likes and when I left on a trip for a month or maybe it was two she developed a strong sexual relationship also. i can't say anything because we are best friends so its not like she's cheating on me and I haven't told her I have feelings for her either for fear it will end or make our friendship awkward. The guy is all she talks about now, how good he is in bed, and how in love she is with him. This really breaks my heart to hear because its like she's forgotten about all the time we've spent together. I don't know what to think when she says she loves me. Is it as a friend or as a lover/ girlfriend? Is she maybe confusing lust with love? Is she in love with me and is lustful for the guy she met? I am so confused right now.