I worked, on and off, as YoungSon was growing up. He was in school only for about 3 months, 3rd grade if I remember right. Generally, we unschooled. I only worked for a couple years that he was too young to be unsupervised, and my Mom lived with us during that time, so childcare was not an issue. YoungSon is now 17, and attending mainstream high school. And I am working; have been for the last 3 years. BigGirl, 18 now, was also at home, so he was not alone.
Finances are obviously the biggest obstacle for most families. I had a few home businesses over the years, with varying degrees of success. I accepted state assistance and financial aid while I was in college (online, so I could be home). I had therapeutic foster children for about 5 years - that brought in some money, but the real reason was that I learned that I am pretty good at parenting high needs kids. I raised and trained baby parrots for a while - until the economy tanked, and people stopped buying ridiculously expensive pets. I made baby clothes for sale at a local craft market and online - that was fun because the kids, even foster kids, could help run our booth. But lots of work for very little profit. I tried to start a board and care home for elderly and disabled residents - the idea was that my kids and I could live and work together. Although I put my life savings (and my heart) into it, my business sense was not up to the task, and it failed pretty dramatically. Bancruptcy and foreclosure; the whole deal.
Somehow, we all got by, and I attribute YoungSon's remarkable progress to the fact that he was not pushed to go to school when he could not handle it. In addition to ASD, he had serious anxiety, and being away from me increased it exponentially. That pretty much resolved itself when he was around 14, and today he is as independent as any teen. Today, I work full-time at a job I love. I totally get what you say about being fulfilled, and the break from the chaos that home can be with special needs kids (at one point I had 6 at home - my 2 near-teen Dumplings, 2 high needs foster kids, and my infant and toddler grandchildren). It was exhausting! It was a relief to go back to work.
My suggestion would be to see if there is anyway you could take a sabbatical or leave of absence from your job. A year, or even a few months, to see what life is like. Casual, low-stress homeschooling, a time to see how your kids (and you!) fare with lower pressure and fewer expectations. If you decide to go for it long-term, there are ways to make it work. But if you can give it a try without closing any doors, that would be even better. And knowing you had an escape plan would lower some of the pressure. Another important aspect of not working at a job is social - plan for some adult interaction, daily or weekly. In addition to purely social things like a reading or knitting club, there are support groups in some cities for families with high needs kids. Some people find connections in these groups, but for me - I needed to get away from talking about my kids as much as I needed to vent about them! Is there any way you could stay in contact with your job, work part time from home, or as a consultant? I have no idea what sort of work you do, but sometimes a little creative thinking can work wonders.