So, I just went out to the shops and on the way back I saw the girlfriend and I thought, "Now's my chance." I asked to speak to her and I asked her, "Am I going to be harassed every time I leave my house or come home?"
The upshot is, she took me up to speak to the guy as I felt better with a mediator there.
Yep, he was drunk. He said, "That's no excuse and I would have phoned the police if I was in your position, and I can't apologise enough."
I could see he was genuinely embarrassed, and while he was attacking my front door he knocked the doorbell casing off, which I only just noticed. Anyway, he said, "I don't care if your doorbell was broken anyway, I vandalised your property so I'll replace it with a new one."
No, his apology doesn't make it all fine and dandy, but we're speaking again, he apologised, and I feel a lot safer in my own home now.
Of course we've all said "I'm never drinking again," and even if we do get drunk, that doesn't excuse wrong behaviour, which is why I owned it and said it was me who phoned the police, and why, and what I said to them. In the end he said, "I wouldn't blame you if you did have me charged."
It's hardly a perfect situation but it's the best that could be expected.