I think I'm in love with my best friend?
So I've had this guy as a best friend for about a year now
He used to hook up with my other best girl friend a long time ago and she developed feelings for him and told him about it but he never felt the same way back for her because he was still now over his ex girlfriend and still isn't over her and she was upset about it but nothing came of it and they ended up just being friends and we all hang out with the same people. Ever since then me and him became best friends and we talked to each other about everything and back in the day my friends told me he had feelings for me but I didn't feel the same way and I ignored it and he never said anything to me about it and never made a move. Even my best girlfriend knew it and said to me she wishes she never hooked up with him because she feels that me and him would be perfect for each other but I said to her no because I didn't feel that way about him. And as my best friend I would go to him for advice with guys all the time and talk to him about my problems. Then time went on and people stopped telling me he liked me and whatnot but we were still close as ever, then recently me and my best girlfriend who he used to hookup with just got a place together and now live together. Just recently me and him got into our first fight ever over something very stupid but it was bad, he said really nasty things to me and called me horrible things and it hurt me bad and he even made me cry and we didn't talk for about a week. During that week it made me realize how much I care about him. I decided to be the bigger person and asked him if we could talk and we did and he apologized and we're now friends again but it's different now, I think I now have feelings for him which I never did before and every time I see him now I'm attracted to him and it's never been like this before. The problem is I don't want to say anything and ruin our friendship along with my friendship with my best girlfriend who I live with because I know she still somewhat has feelings for him too. Can I please just get advice on what I should do?
I feel like a terrible person because I know my friend would hate me if she knew I've developed feelings for him but she knows that we're best friends but she's convinced that I have no feelings for him but she's also convinced that he does have feelings for me. He knows that she has feelings for him and that she would hate him and me both if we ever did anything together and she were to find out because her and him used to be something although they are nothing anymore. I feel like I lost my shot with him because so much time has went by since he has liked me but I do have some hope because maybe he's just hiding his emotions because he feels like we can be nothing because he knows that my roommate would never let it happen? I would just love to get some opinions because I've been keeping it all to myself and I don't know what to do at all and I know this is the only place I could say this without it getting to anybody