Hey OP,
Poon king is right. You're waging a waste of a battle.
As long as you're emotionally invested and trying to "make things work" your neediness will repel your ex girlfriend like a goldigger in skid row. You may not think your neediness is apparent, but to your ex it's only all too obvious.
Just the fact that you're still calling her up and trying to make things work with a woman who dumped you is more than enough to break 100 on the neediness scale.
You need to move on. Once a woman breaks up with you, the relationship will never be the same. Instead of trying to make things work, she has decided that you're not worth the effort of fixing things. Is this the kind of person you want to spend your time winning over?
Go out and find a woman who actually appreciates you and all your good qualities. Let this woman go out and find out just how much douchebags guys can be. Then one day, she will look at her relationship with you with regret and she will wish she had made things work.
However, this will never happen if you continue to "try to make things work." By continuing to do this after she has dumped you, she is just subconsciously confirming in her mind that dumping you was the right decision. Women are hardwired through millenia of genetic and environmental conditioning to be attracted to men who are strong, independent providers. By showing her that you can't live without her, you are providing her with the exact opposite qualities that women are naturally attracted to.
So, while I can't emphasize enough your need to leave, I will give you some pointers on what to do to possibly try to turn things around. If nothing else, you might regain some self respect by winning back some power and "the upper hand" and at least you won't feel as bad as you do now.
So here' s the list:
1. Don't make yourself too available to her. Start chasing other women, start doing other activities
2. When you do text her, keep the messages short and sweet. Don't be asking her to meet up. This will show her that you can live without her. Women are naturally attracted to men who are just out of reach.
3. Don't bring up getting back together. Just focus on being fun and happy. Flirt, but not too much. If she responds favorably to flirting, keep going and try to seduce her. If she doesn't respond favorably, cut the conversation short and go ghost.
4. I don't believe in playing games, but after you've been dumped this becomes necessary. You need to show her that you're happy with her decision, and that you're having a great time without her. That you're even enjoying yourself more without her. This will make her think "what am i missing out on?" and "why isn't he chasing me?"
5. Don't buy her gifts/offer to take her to dinner: this gives her the impression you're trying to buy her back. Gifts during a relationship are ok, but after you've been dumped you need to stop doing this.
6. A little jealousy never hurt. Drop hints about how you're doing this or that with a "friend" or "friends." But don't flat out tell her you're fvcking other girls, or this may end it for good (and you should seriously start thinking that this would be a great thing).
7. Always observe the last messager rule. Girls know this rule well. The last person to not respond holds the power. So always let her be the one who messages last. Always be the one to end the conversation, and end every conversation at its high point. Observe the well known rule in entertainment "always leave them wanting more." This rule exists for a reason. If the conversation is suddenly starting to go nowhere, end it immediately.
8. Once in a while, cut off your conversation with her by saying "anyway, gotta run. Meeting up with friends at so-and-so place. Talk to you later!" This will naturally make her more attracted to you, by showing her that you have other things to do and you don't need her in your life. She will start thinking "what am i missing out on?" and "why isn't he asking me to do these things with him?"
Now, you can follow my advice and continue to play relationship calculus with this ungrateful woman or you can cut her out of your life, focus on healing and getting yourself better, and trying to get a better and more deserving woman for yourself.
The choice is yours.