It’s a fact that she dumped you and moved on instantly.

But, I worry, at this point in how you are obsessing about saying that she definitely used you for money and was a manipulator. I worry you will harbor anger, obsess about it, and maybe start to feel vengeful. And from what you told us here, we are only hearing one side of the story and speculating she used you for money.

Plus, as I pointed out earlier, it was your bad choice to give her money that you needed for yourself, in hopes of maintaining a relationship.

It’s a break up. Break ups can be cruel. They really hurt. You are grieving. With healthy thoughts, you will move on.