Hang on- the OP just said she WBU! Has she not realised this is AIBU?! Is that even allowed?!
Anyway, I'm still pitching in, fwiw. I'm lucky enough to have a DH who works erratic and long hours, and frequently has to leave the country at the drop of the hat. We don't know from one day to the next where he'll be, and I've never been able to rely on him being home at a set time.
Added to this, the fact I have no family support or childcare has meant, as Startail said, taking the path of least resistance. My youngest also starts secondary soon, and I'm looking at courses which may lead to some sort of (self) employment. This may or may not work out, but, again like startail, it's so long since I've worked now I can't see me being selected as an employee for any job I'd want to do.
Maybe that's another reason I'm lucky I don't have to stack shelves or wipe arses, but, again, it's all in the interpretation.