Well ... any break-up is awful and it hurts at any time in any circumstances, so you have my total sympathy and big hug. But one of the things we have to accept, however hard it may be, is that most heterosexual women want a 'normal' heterosexual man who is absolutely 100% certain of his own masculinity. When we tell them the truth about ourselves, it can often (not always, but often) disturb them, upset them and makes them feel short-changed. That, I'm afraid, is just part of the deal that comes with dysphoria. Totally sucks, I know, but it's not her fault if that's how she feels. It's just life.
But I know that doesn't make it hurt any less ... so have another big hug ... I feel for you, I really do ...