Managing Mental stat is extremely difficult... There are tons of ways to decrease it and very few ways to increase it, which all take a lot of time and are random events. I've already needed to reboot once... speaking of, I apparently need to pay 1000 credits after a reboot, but I don't see a way to do that? Is it because I don't actually have 1000 credits to pay? It doesn't appear to be locking me out of anything, though.
EDIT: Ah, there are Perks to help with managing Mental. I just hadn't hit Level 1 yet, so I didn't know about them. Still, if I already had a reboot before hitting Level 1... seems really hard to manage. Also... I can't tell if Servant Mentality is, uh, actually doing anything... I assume the gain is just lower than the decrease, but they're not delineated, so it's impossible to tell.
EDIT 2: Okay, owing money just locks you out of using the clinic.