Denial is common wherever childhood abuse and neglect by a caregiver was involved, regardless of the diagnosis bestowed upon you by people who profess to know how you the human had to adapt your being to survive the experiences thrust upon you for years on end. The child of three or four needs to figure out a way to get through the next 12 or 14 years with as much of themselves as intact as possible. That means getting as much of the normal stuff as they can eke out of whatever awful situation they are in. That means separating/forgetting/denying the bad stuff, because what child wants to be looked after/sit at the breakfast table with
Denial is that young child's friend. Denial enabled that child to grow, to learn, to laugh, to live, to love, wherever and whenever it could. Denial enabled that child to take in some of the good stuff and grow some semblance of normal self, even when other parts of self were terrorized and beaten down and murdered in the night. Whenever things became too hard, denial helped everything be okay again. At least, until it wasn't. Denial is like a time-out, a gift, a breather.
So today you "don't have DID" (or PTSD, or complex PTSD, or OSDD or whatever you like). Maybe it's okay to just sit with that. Maybe some part of you (not necessarily an alter, but it could be)
needs to not have DID today (or PTSD, or complex PTSD, or OSDD or whatever you like). Maybe some part of you just needs a break. Maybe you don't even need to worry about whether it is real or not, but just work with whatever comes up. If you have it, it will "come back". Something will trigger you and there "it" will be. And if not... then you can just work with whatever is there.
But you know... denial is awesome. It's a big job. But somebody's got to do it. It's there to help.