I understand that you want your ex. back, and you have apoligized repeatedly. Only your ex. isn't biting. This is because there is more to this story than meets the eye.
First of all, your ex. seems to enjoy torturing you and watching you squirm. The more you beat yourself over the head with self-recriminations and apologies, the happier she is. In other words, what you are doing isn't working to get her back. What you are doing, I'm afraid, is satisfying a deep need that she has to punish someone who she believes victimized her.
What you aren't seeing here is that your ex. has played a role in creating this problem. What she doesn't see is that she arranged to become your victim (and to turn you into the bad guy). How? By silently allowing you to have intercourse with her when she didn't want it. Then, months later she comes out with this information and makes you into the monster. But, she isn't taking responsibility for her silence. Nor is she accepting responsibility for consenting to intercourse that she didn't want. She condoned the intercourse, stuffed her anger, then blamed you for forcing her. Where was her voice all along? Why did she consent to intercourse if she didn't want it? My point here is that you have been set-up.
I have the impression that your ex. was' victimized' in the past and that she never worked her feelings through. And, without her knowing it, she arranged to allow you to 'victimize' her. This has served two purposes for her: It helped her release the feelings over the previous abuse; and it enabled her to rewrite history and become the powerful person (by dumping you). At the same time, she deposited her feelings of victimization onto you (now you feel bad and guilty and beaten down).
Because you want her back, you have been willing to assume the 'guilty' role that she is demanding you to play. But, as you see, continually begging her forgiveness isn't winning her back. She is getting too much gratification to release you from this hotseat.
So, what can you do? Try something different. Stop attacking yourself and tell her that you've had a chance to think over what went wrong and that you have a new understanding.
Tell her that you have the impression that she felt like a victim with you. She stored up a lot of anger and then, finally, when she couldn't take any more, she dumped you. Ask her if that sums it up. When she says yes, you could ask her if she is interested in knowing what role she played in these chain of events. If she says yes, then you can explain to her that by never telling you how she felt about intercourse, and silently allowing you to do it, she made herself into your victim. If you can help her to take responsiblity for her role in this scenario (instead of simply viewing you as the bad guy who needs to be gone), you may have a chance to rebuild this relationship.
Good luck. If she is willing to examine her own need to remain a victim, you have a chance to win her back.