I honestly don't know how I do it - but I have worked all of my adult life except for one really bad year about 8 years ago where I couldn't leave the house.
I work in Human Resources on the staffing side, so I get a lot of alone time in my office and my interactions are typically with people I know and respect. I've been at my current location for just over a year. I have moments, hours, days where I just can't cope and that is when I shut my door or call in sick. I have been lucky enough to space them out enough that people think I just have bad luck with getting sick.
I just recently came off of a 3 month leave of absence however, because I felt like I was losing control. New meds and an actual correct BP I diagnosis helped but I still feel like I am "pretending" when I am at work.
I can imagine not working comes with guilt - I had it while I was on leave. But there is a subtle balancing act that comes with working and it is not an easy one to maintain at all times. I often feel like no one here knows the "real" me, that I am pretending all day long to be happy and outgoing. Unless the mania is taking over, and then I AM happy and outgoing!
In summation - work is a juggling act. It's stressful and sometimes harmful. Do what works for YOU and your situation.