I experienced similar crashes in single-player scenarios due to mods. When several mods are installed, it sometimes happens that you play peacefully on a map for a while, and then a conflict with a mod occurs, resulting in a crash. Therefore, I recommend first removing all mods (and unnecessary maps, because they may also contain mods), and then starting the game from the beginning.
And also... In principle, it's not necessary to play all the way to the tenth month ;)