Wow, what a dick! Seriously. It’s blowing my mind.
But I tell you what I think it is (and PPs have brought this up; I think they’re right):
He went on an extended stag party, and the “boys” convinced him that he was too young to get married, and why would he want an old ball and chain, and do you really want to be with the same woman the rest of your life when there’s all this hot tail walking around for the taking?
These things are all ridiculous and untrue. But generally guys don’t start realizing that until they’re about 25 or so. There are a rare few who get it before then, but it’s really rare and far between.
He got scared, and he wasn’t man enough to admit he was afraid, or that maybe he had moved too fast or made a mistake. So he started telling his dumbass friends about all the things that were wrong with YOU. Dumbass friends, not wanting to lose him to a 23-year-old guy’s idea of what marriage is, backed him up, saying you were all the things he said you were. And OP, he may have even told lies about you to them.
So then he shows up and is an asshole to you, because when you’re male and 23, it’s really easy to mix up confidence and assholery. He might have even heard enough back-and-forth BS from his “bros” to have convinced himself that it really was your fault. The worst part is that he was disrespectful of your parents. That’s LOW. There were plenty of ways to accomplish what he wanted to accomplish without doing that, but that would require him to actually man up, and there apparently wasn’t enough man in him for him to muster up. So he took the coward’s way out and was mean.
His friend then said he would “destroy you online.” WTF does that even MEAN? Does that mean he’s going to give 4chan your address? Is he going to tell his World of Warcraft guild that you’re a slut? That’s the most ridiculous threat I’ve ever heard. “Hey, I am going to do you harm, but I don’t have the balls to do it without the shroud of anonymity the internet offers.” What a tool. If it were me, I’d call his bluff just for fun, and not only that, but I’d screenshot the image of his texts and post it to Facebook. LOLs go both ways.
But–after all this, you still miss the guy. That sucks, because PP are right–he will get lonely, especially when the dickless friends of his start pairing off and he’s alone. He will come sniffing around with his tail between his legs, looking for a warm place to put it for the night. DON’T GIVE IN. If you do, you only reinforce his horrible behavior, and worse, you’ll be dishonoring your parents. Let him suffer like you’ve suffered, because that’s the only way he will learn. And then, if in at least five years, you have reason to believe his balls have dropped, you might be able to give him another chance. But make him EARN it with every ounce of energy he possesses. Then tell him no and make him do it again. What you choose to do after that is up to you, but it’s my belief that if you keep him at bay until you’re 100% over him, the next time you see him you’ll be with someone much better, and he’ll get to drive home with tears in his eyes, and Adele’s “Someone Like You” on his stereo.