Could really use some honest opinions right now

Ok soooo heres my situation that has led me to this site. Theres this girl who I have a long history with, we talk pretty much everyday sometimes about nothing, other times she will come to me when she is having a bad day just to vent and what not, and the odd time the conversation becomes more serious (i mean feeling stuff). She knows how I feel about her, I made sure that I was very clear on that with her. She has told me how much I mean to her and that I'm very important to her ect.. but I can't just be friends with her anymore, and I've told her that. But when I have told her that we should just part ways and say our goodbyes she gets all upset and tells me that if i left she would be devastated, then she found out I was going away for a few weeks she was about to cry, she also told me that no one could replace the way my eyes can look deep down in to her heart and soul. But I cant help but feel like I should just say my goodbye even though its a hard thing to do, it feels like it might be for the best. I would give anything to be with her, but I'm honestly just so confused about what to do. she says she doesn't want to lose me but she wont be with me.

why don't you just be friends but not talk to her or hang out as much? it doesn't mean you have to walk out of her life forever just because she doesn't feel the same way romantically. I would try to lessen contact, don't talk to her every single day or every time she texts you, but still remain friends and see each other now and then. this way you can move on and meet someone new but still be a part of each other's lives. it's not really the same as a breakup because you guys never dated, but I understand how tough it is to try to remain friends with someone you have strong feelings for. I would try just slowly weening off of her