How do I deal with losing a whole season to weather I cannot control?

You gave the land everything, and a stretch of bad weather wiped it out anyway. That is a particular kind of grief, because the loss is not from carelessness. You did the work right and still lost. It can make all the effort feel pointless, like you are gambling your labor against a sky that does not care. Anyone who works the land has felt this, and it is a heavy thing to carry. Here is the truth the best farmers learn to live by: the harvest was never fully yours to promise. Your job was the effort, not the outcome. The weather sits entirely outside your hands, and it always did, even in the good years when it happened to cooperate. Judging yourself by the yield ties your peace to something you cannot govern. Judge yourself by the work you controlled, and the ground under you steadies. Right now, tend to what is still in front of you rather than the ruined field. Take one concrete step toward the next season, save what seed you can, repair one thing, walk the land and plan. Action is the antidote to that helpless feeling. The season is lost. You are not. Give your effort again, and release the rest to the weather, as you always must.