Andy, I am so truly sorry. I realize this doesn't help with the heartbreak you're going through, except to say I went through very much the same thing once upon a time.
Getting dumped while in a hospital bed (all the while trying to come to terms with a new, very frightening disease) has to be about one of the worst things that can happen to a person.
So I'm not going to say things will get better, or good riddance, or any other cliched platitude, because deep down your heart got whalloped. Just that I'm terribly sorry.