He then sped up behind me, cut me off into the gutter, got out of his van and offered to fight me. I told him that if I can touch his van then he's too close and that if I told him to fuck off then it meant I didn't want him near me, let alone fight him.
This sort of altercation fucking depresses me. Like when that first (and almost certainly intentional) close pass happened, you're just meant to suck it up and not make any sign that the driver was doing something invasive. The proof is that they immediately were looking in their mirrors at you when you gestured 'wtf?' - basically baiting you.