Up front, my experience probably isn’t going to be much help, aside from validating your experience. I’m up shit’s creek and have been for quite some time. To hit your numbered list first:

1. Yes. So much this. A lot of it likely comes from childhood, where unless I was puking I was “faking it” because I had earned the “lazy” label thanks to early academic aptitude and subsequent failure to complete assignments (undiagnosed AuDHD). “I’m not dying, I should be okay. Instead I’m sitting here doing nothing.”
2. Unless you’re running the business this should never be a thing… but as we all know this is all too common in an office setting. The longer you’re out, the more backed up you get, to the point where even planned vacations are stressful because in the back of your mind you can see the accumulating workload. It’s by design and it makes me want to flip tables.
3. I’m only recently getting a good read on my past and present experiences with autistic burnout (which is absolutely its own thing but thanks to the lack of interest in studying adults the only language we have is “it’s like burnout, but turned up to 11”). It first hit (as an adult, anyway… childhood still needs to be unpacked) a mere year into my professional career, trying to navigate a high level of technical challenge (since I was green) and a high level of social challenge (field service work in and around a dense urban area). The most recent was the culmination of 11 years of hard work being rewarded with more work and more responsibility, and getting hung out to dry when it overwhelmed me. Probably the last 4-5 years of that was me “pushing through” burnout, because I simply had no other frame of reference and bills needed to get paid (this is “real life,” I don’t have the energy to look for something else, bad economic time to be the low man on the totem pole, better the devil you know, etc.). It got bad. I left two and a half years ago when they tightened the screws enough that I could no longer pretend. I had like 6-8 months of expenses saved, my spouse had steady work, and the plan was to take time to recharge and worry about the gap in the resume later. The recharge never happened, thanks in no small part to life continuing to pile on. The only upshot to this is that I’m finally getting some real therapy, after years of off and on bad experiences with prior attempts.

To kind of sort of answer your questions:

• Do you have difficulty identifying burnout?

Yes. And so do employers. Individual managers may care on a professional level, maybe even on a personal level. But the business itself is incapable of caring. A burned out employee will simply be replaced once they no longer produce. The added nuance that autistic burnout brings to the table is a “you problem.” Yes, I am bitter.

• Do you have difficulty identifying when you’ve recovered?
• How do you decide when to go back to work?

I realize this kind of response is unhelpful, but that’s where I’m at right now. I’m trying to unpack things through therapy, but life doesn’t get put on hold just because I can’t handle it. And being in the US isn’t helping, what with all the make believe rugged individualism and the gubmint doing a slash and burn on social services. I feel like I’m on a trajectory to starve in the streets as opposed to recovery. I am still trying in spite of it. I’m exhausted though.

I wish I had better answers for you.

Honestly, I mostly let my psychiatrist decide. She asks the right questions and we figure it out together.

Other than that, if I’m dreading work more than usual, I’m probably sick. Same if I’m experiencing physical symptoms, like a sore throat, headache, unusual fatigue, aching body I’ve decided it doesn’t matter if it’s autistic burnout or a minor virus. Both are valid reasons to take sick leave.

Edit: I should point out that I don’t have an official psychiatric diagnosis for autism, just one from a psychologist. So what I’m being treated for is ADHD and literal burnout syndrome.

Burnout is a common experience for those of us with ASD. Autistic burnout in particular was only formally defined in 2019, even though the concept had existed for a couple of decades prior.

In your case I’m wondering if it’s the more classic occupational burnout since you’re feeling up to hobbies (which presumably you enjoy?) after just 48 hours away from work. My personal experience with autistic burnout is that it is really hard going and takes a long time to slowly climb out of.

I find it useful to distinguish between getting overwhelmed (which eventually will result in a meltdown) and burnout itself. Think of it this way: burnout drastically reduces the cognitive resources and energy you have available to deal with life. Effectively that means your available “bandwidth” to manage both sensory input and cognitively demanding situations is vastly reduced. That makes it much easier to get frustrated or overwhelmed. The reduction in cognitive resources also means that our ability to mask breaks down, so we more readily upset people (particularly NTs who don’t understand autistic behaviour).

On the work front, I can empathise with points #1 and #2 (not so much #3 as my interoception is apparently quite acute; if you struggle with determining your internal state then I recommended looking up some exercises to help with this, as you can improve it through practice). For years I was the single point of failure at my workplace so I was carrying a lot of stress. There were plenty of tasks that if I didn’t do them, nobody else could/would; there were also time-critical things that if I didn’t push myself to do in time, I would inevitably end up dealing with the clean-up. My manager did his best to work with me to reduce my workload (I even worked part-time for a while, much of work-from-home), but I was already too burnt out for this to enable me to recover. I eventually collapsed in a heap, prompting my employer to hire additional staff. My (very slow) staged return to work has started with just some knowledge-transfer and advice meetings so that they can continue working on the projects I’ve been involved with.

Determining when to return to work is not easy and it depends on how badly burnt out you are. If this is a repeated issue with your workplace, then I’d encourage you to talk to your manager/supervisor (if you can) to flag that the workload (and/or environment, if it provides high sensory input) is pushing you into burnout on a regular basis. It is in the interests of the business to avoid doing this, as it means you don’t work as effectively when you’re burning out and then have to take time off to recover. Usually employers can provide accommodations or restructure the work to some degree to help. The goal should be to avoid you burning out again, as not only is that the best for you and your health, but also gives your employer the best outcome (a productive, reliable employee).

You mention work-from-home, so that’s something to look into further - if your job allows (and your home environment is less demanding than your workplace), you could either try to get a regular WFH schedule or have a staged return to work starting with lots of WFH and slowly increasing the time in the office.

I don’t know if this applies to you, but I find meetings very draining and so avoiding back-to-back meetings is essential for me at the moment. If you have regular meetings, see if you can arrange with your colleagues to space them out a bit to give you time to recover inbetween.

On the home life front, prioritise your health. Sleep is crucial and anything that disrupts it must be addressed. After that focus on nutrition and exercise, but don’t push yourself - that only exacerabates burnout.

The toughest part of all of this is going to be learning to pace yourself. It takes time and practice to identify how much energy or bandwidth you have for a given day and how much you can realistically achieve without making the next day a write-off. Again, if you can look into some interoception exercises to help you better judge your internal state, I think it would help with this (and eventually help you prevent burning out again too).

Don’t know if this helps, but I will share my experience anyways. I left my job last August, sparing the details it was unbearable. I am just now, climbing out of the hole. I have been busy continuing my education in the meantime and working to improve my marriage and immediate family relationships. It has been an experience. The way I judge is to gauge my interest and pleasure in activities that I formerly enjoyed before falling in the abyss. When I am burnt out, nothing is enjoyable and I find pleasure in almost nothing, except sex. So I would say watch out for changes in mood and confirm changes in behavior, if things get really bad it might take 6 or so months to stabilize. From my perspective, it’s all about having the resources to fight your battle, and most people lack the resources when they need them. Survival is the key, bide your time, stack your resources and make your move. It is never too late. You are not doomed.

Sounds familiar, lmk what y’all find out, I’ll bookmark this and promptly forget about it.

Talk to a professional. Burnout at work is often a result of caring about something that is out of one’s control. Which means that just getting some rest and coming back into the same environment will bring the burnout back.

In other words, you need to rest, but also change the pattern that led you there. Unfortunately changing jobs will likely mean it all will come back. It’s not your fault, but only you can learn to do things differently.