I screwed up and ruined everything for good this time.
No, you're OK! We all backslide now and then. Don't freak out, it's salvageable! Just remember, his emotions are running things right now. He'll say mean, hateful things. That doesn't mean there's no hope, you've just got to stick with DB'ing and work on yourself. He needs time to sort through his thoughts and emotions. You need to give him time and space. At this point he knows your position, so don't put any more pressure on him. Just give him room. Work on improving yourself. It is REALLY important to have a PMA around him right now, even if you're faking it at first. Don't be down and depressed around him, you want to be beautiful, upbeat and happy! Dress up, look your best. Change your hair, whiten your teeth, update your look. Do it for you, but rest assured it'll get his attention. Get out on your own more, see friends. Be mysterious. Don't make this about him, make it about YOU!
And if he draws you into an emotional convo in the future, remember not to argue with him. You need to validate his emotions rather than argue. Tell him things like "You sound like you've given up on our M, you sound frustrated and I can understand why you feel that way, I'm sorry for my part in your disappointment and frustration." You're not agreeing or disagreeing with his position, just validating his feelings.
There's always hope! Don't get discouraged, there will be many highs and lows. You're barely over a month since BD, his emotions are still going to be in high gear for months yet. Take a deep breath and settle in for the long haul. Good luck!