Try following the "2 second rule" plus because it was dark and wet consider extending that to three or four. Clearly you have NO clue of a safe following distance...
Furthermore, fix your imbalanced front headlights and for god sake fix your rear tail light.
Oh and I am glad I stopped to let you by....your van even though it just about passed it's 2015 MOT still has shitloads of advisories...more worrying is a number of them are related to a "temporary fuel cap" (diesel in this case which if spilled poses a huge issue to cyclists, motorbikes and RWD car drivers) plus your brake problems, considering you are certain of yourself to follow at such distances with such appalling repair levels of your van I am glad I let you by!
For those reading, it originally got in 2015, RfR's (failures) and advisory for:
RfR:
Reason(s) for failure
Front passenger door cannot be opened from outside the vehicle (6.2.B.1b)
Nearside Rear Body or chassis has excessive corrosion, seriously affecting its strength within 30cm of the body mountings (6.1.B.2)
Offside Rear Body or chassis has excessive corrosion, seriously affecting its strength within 30cm of the body mountings (6.1.B.2)
Registration plate lamp not working (1.1.C.1d)
Nearside Rear position lamp(s) incorrect colour (1.1.A.3e)
Battery insecure (1.9.1)
Front Windscreen wiper does not clear the windscreen effectively (8.2.2)
Windscreen washer provides insufficient washer liquid (8.2.3)
Exhaust has a major leak of exhaust gases (7.1.2)
Brake load sensing valve seized (3.6.E.3)
Brake load sensing valve linkage defective and function impaired (3.6.E.3)
Brake pipe excessively corroded (3.6.B.2c)
Nearside Front Shock absorber has an excessively worn bush (2.7.4)
Front Brakes imbalanced across an axle (3.7.B.5b)
Advisory notice item(s)
Nearside Body has slight corrosion (6.1.B.2)
Offside Body has slight corrosion (6.1.B.2)
Steering system has slight free play detected at steering wheel (2.2.A.1b)
Rear Anti-roll bar has slight play in a pin/bush (2.4.G.2)
scratches in windscreen
Temporary fuel cap fitted
(None of the advisory stuff has been fixed!)
Judging by the previous history of your vehicle as well....poor repair throughout.
Ever get the thought you might a bit close to the vehicle in front....I drive an MX5 as well and this was taken from my Go Pro try re learning stopping distances and the two second rule idiot.
BMW Z4 - Decent driver, courteous, polite, a rarity nowadays.