I kinda know the feeling. It's tormenting when you want to be as special to someone as they are to you.
As painful as it is, the only advice I can give is be honest. If you're craving something romantic between you and this friend, then come clean about it and if she doesn't feel the same way, then, as painful as this choice may be, move on. There's always a stigma around whether or not you can continue to be friends with someone you've had feelings for and from my personal experience, it doesn't go well. At this point, it sounds like you no longer really want the friendship. You want romantic connection. If she's unwilling to provide that, then the deal that's currently between the two of you isn't in your interest anymore. It seems harsh to put it like that, but it's the reality of it. I'd definitely also say that it might help to work on your own emotional grounding as well. There's nothing wrong with crying but crying consistently means that there's still a problem within that you haven't sorted. Even if it means you have to spend hours crying and mulling over a circumstance to come to terms with it, it's better than it constantly coming back to haunt you.
Hope this helps.