Isn't the whole point to give her a clear message that the relationship is over?
You can't have it both ways. You can't say it's over, go back to your boyfriend, we can't be friends etc. and then wonder if she really means she's interested, because she might call.
Why don't you seek out counselling to help you put this relationship in perspective. It's time to get off the merry go round, make a decision, and move on. Really move on. As in life is short, don't waste your time on 'what if relationships'.
When you posted for advice, people generously and thoughtfully gave you their opinions, but your last post has given the impression that you are talking the talk, but you're not walking the walk.
Time to tuck this relationship into a little box in your brain. Put the box in a vault, and lock it up tighter than the Royal Mint- with its contents, including the emotional ones, which are are off-limits, and not accessible. Because, if you try the combination, the entire thing is going to explode in your face again.