>>513507922 (OP)>How should we fix the single mother problem in society?The answer to this is another question; what circumstances create single mothers?
Personally if I were to guess, I would say there's probably twin forces of men not being able to step up to fatherhood until later in life, and women being able to avoid men while raising children; the latter answer having multiple factors.
For men, we could therefore fix it by making sure men have lots of resources so they feel comfortable stepping into that role no matter when it pops up.
For women, we would need to fix a few things. Women have too much access to resources without a man's approval, those sources could be removed. Women have too much social leeway to fuck around thanks to birth control, we could remove that as well and try to create shame for fucking around unattached. Without resources for raising the kids, denied any social status and with limited ability to prevent pregnancy, women would make more extreme efforts to be locked into a steady (marital) relationship prior to having sex and potentially breeding.
The answer that everyone hates is that women need to be pressed back into dependence on men, at which point they will fall back in line and do what they should do. But it isn't even unfair. Strong independent modern women don't live without support from men for the most part, they get shittons of government bennies, they just don't get those bennies from any particular man. Removing government bennies won't change their basic existence, it will just reveal that existence for what it actually is, a transfer of wealth from men to women.