The silver lining here is that your brain is simply trying to do its job. "The phenomenon of Sunday Scaries boils down to a preemptive fight-or-flight experience that signals our adrenal glands to flood our body with the stress hormones adrenaline and cortisol," says Silvestri. "When our psyche picks up on these signals, we begin to ruminate on all the reasons why this dread is gripping us. Now, a self-sustaining cycle has commenced in which we feel physiological stress, use our mind to provide the reasons for said dread, then feel more stress and off we go headlong into the Sunday Scaries." This, dear readers, is what we refer to as "spiraling."
I brought up loving my job earlier because it's important to note that the reasons for this onset of anxiety might not always feel totally obvious. (In fact, as Silvestri notes, feeling like you shouldn't be anxious only perpetuates the spiral.) If you think about it, our culture has set us up to view weekends as playtime and weekdays to be more sanctimonious in ways that extend far beyond work.
There are other errands to run, work-adjacent functions to attend, alarms to abide by, and workouts to log. On the flip side, says Silvestri, "we see ourselves potentially overcompensating on the weekends by drinking too much, playing too hard, accomplishing and thus savoring too little. The deck then is stacked against us when Sunday evening rolls up and we are having a serotonin crash and now realize the party is literally over. Contemplating a workweek of renewed deprivation and compensation is enough to send anyone into a very unpleasant state of dread." And even if the most hard-core thing you did all weekend was binge-watch The Walking Dead, a week of not lying around can be a tough pill to swallow.