I had a similar experience.
When I first got out of college, I worked for an ancient coin company. Started as a temp, ended up as an administrative assistant 4 1/2 years later. Was loyal, too, despite increasing evidence that the company was shady, that it might go under, and that the company did not deserve, and would not reward, my loyalty. Watched most intelligent co-workers with any kinds of options leave.
In January of 1994, I finally decide that this rat doesn’t want to be the last one off the good ship “NFA”, so I look for options. I take an exam to attend a paralegal program–to become a paralegal.
The day I find out I’ve been accepted into the program (and would have to quit my job to attend, which I fully intend to do as soon as everything is confirmed), I get laid off. This essentially allows me to pay off my school fees with my unemployment. Not too many people like to be laid off, but this ended up saving me $3000 or so. I would not have been able to have collected unemployment if I’d quit.
Program runs from January to June. While I’m going through the program, a newspaper article alleges that the company is in serious financial trouble. The owner (a former owner of local NHL team) calls a meeting and GUARANTEES his employees a position at least through the end of the year.
Now, I was not aware that the year ended in May, but apparently, to his way of thinking, it did. Because EVERYONE was laid off in May. Much like Alantus’s post above, one day, the company existed. The next day, it did not.
While I certainly felt for my ex co-workers, I thought that anyone who believed the owner of said company was being naive. Especially because the owner went to jail for loan fraud. As did MOST of the high ranking people in his organization. Far as I’m concerned, he deserved it for lying to his employees, some of whom had been loyal to him for YEARS.
Re the OP: Again, the impulse has been there for me to flip someone the bird, and never return. It usually isn’t worth it, though. Plot your escape ahead of time, if you can. You’ll still have 95% of the satisfaction when you DO give notice.