I agree.
OP is starting this thread from a place of powerlessness and desperation no doubt (sorry, don't want to put ''words'' in her mouth) but hearing ''you're wrong because I managed it'' isn't very supportive.
OP is basically right, unless you have an ADVANTAGE, be that owning your own house already, or a grandparent who will mind your kids for love not money, or a high income salary that you can either step right back in to or never stepped out of, or a highly regarded and more to the point highly remunerated profession/qualification - then the OP is right. Coming from the current place of being out of the workplace as a lone parent with young children and none of the advantages listed above, it is very very very hard to make it work.
I am making it work now because my children are older but I do remember in fact, starting threads like this, feeling powerless and rejected by society and looking for some sort of validation that it wasn't ALL MY FAULT
Op if you're still there, it is extremely hard to make it all work as a single parent without advantages. Society allows this. Women/mothers pay a much much higher price for parenthood than fathers do and this ''effect'' is magnified for single mothers.
All I can say is that I felt exactly how you felt and eventually, when my dc were teens it picked up again. I still earn less than other women my age but at this point now I don't compare myself to them. I'm starting to feel fortunate. It takes a while.