These red lines.
The problem with self-medicating a low mood with caffeine is that if I do it too quickly, I'm unhappy and fast, and if I pace it out for too long, I end up in too good a mood to want to go to bed at a reasonable hour to counteract the struggles I've been having getting out of bed these last few days.
On the plus side, I managed a fairly decent workout, so there's that.
On the plus side, I managed a fairly decent workout, so there's that.

Thoughts
You might try different sources of caffeine. Coffee tends to hit hard and fast, while tea works slower and smoother because of its different compounds. Energy drinks are worse than coffee. Chocolate is slow-ish but the sugar can also create a spike and crash, unless you're using very dark chocolate with minimal sugar.
Alternatively there are other foods and beverages with mood-boosting effects, that might work instead of or in combination with caffeine to lift your spirits without wrecking your sleep.
no subject
In the meanwhile, I might give the chocolate suggestion above a try - some kind of sugar free vegan chocolate drink could help. God, I've become such a puritan. Ten years ago, I'd just have reached for the Cadbury's.