You need more self-restraint. This doesn't create attraction. The more needy you make yourself out to be, or the less balanced of a person, the less attractive you will be.

If you have the power to walk away, then that can create attraction. Why would a woman who can pick from tons of men pick a man that's incomplete without her? Pick a man that can't get another woman, even one she perceives to be lower in value than herself?

Also, why message a person? If you want a true relationship you need to talk face to face. Messaging is not pointless, but you do it when there is no other way to communicate something important or to make appointments.
If she feels like texting, fine. But as a male, you shouldn't initiate it, I feel. If you both want to talk to each other, call her and decide on a time.

As for your message, she knows you know she doesn't want to talk to you, yet you still message. That's weak. As for saying you will always love her, that's silly. If you haven't seen a person for 10 years, the love will be gone.

Anyway, I see now you say she is your ex. If you two were really serious, and you two clearly broke up, why message? Even more so when you are doing exactly that which is why she says she broke up with you.

You have tried everything? What about not messaging your ex and then when you get some new relationship, make sure you are perceived as someone who can and will walk away when things are not working out, and won't look back.

Sorry if my advice is harsh. It seems you know all this but don't know how to self-control. I have no advice for you there. I naturally have an absurd amount of self-control. I have no idea how to teach others how to do it. I wish I was more spontaneous and impulsive sometimes.