With huge population loss in Ukraine, more than 10 million people fled Ukraine since February, now Ukraine population is less than 30 million. I doubt Ukraine can mobilize 1 million men considering in Ukraine the population is female heavy due to male losses in WW2 which changed demographics.
Welcome to the first permanent war in human history. Permanent. Just like CO2 increase is permanent. Permanent. Just like covid-19 is permanent.
In order for a war to end, there must be negotiation for peace. Neither Ukraine or Russia will ever negotiate. Without negotiation, war cannot end.