I kept it secret for so long. Ironically, throughout all the time I did, I was definitely a lot more unwell than I am now. Overall, I still have many off days.
When I switched jobs, I didn’t advertise it. But I got to know people and I happen to be working with a bunch of nutters anyway, which helps. They opened up to me, so I reciprocated. My bosses don’t know though, they don’t deserve to or need to frankly.
Personally, I’ve found it easier once people know. Some know more of the why than others but most can sense when I’m not having a good day, or if something has triggered me. And they help out, even if it’s “go take 5”.
As with everything in life though, I guess it depends on the circumstances.