Yes, I admit some confessions are particularly hurtful. Especially some people are particularly sensitive. I'm not being stingy, but some emotional concerns are understandable. But, you're breaking up for this? Do you think you are overreacting?
She told you because she wanted you to know everything about her. In the first half of her life, you were always late. I hope you won't be absent in her later days. That's all, that's all. Why did she say it when she knew you couldn't accept it? Lie to you all your life, okay? So, you have to understand her courage. Which is the determination you gave her.
Don't you have your own experience? Will she stay with you when she knows? The answer is self-evident. Take care of your heart, you know.