Ok, I figured it out. I believe that the issue has to do with being in fullscreen. For anyone wondering, if a clean install does not solve the issue:
1) Do a clean install
2) Open file explorer and navigate to "C:\Program Files (x86)\Steam\steamapps\common\Mount & Blade II Bannerlord\bin\Win64_Shipping_Client>"
3) In the path (the top bar where you see how you got to the Win64 folder) type cmd and hit enter
4) Type "Bannerlord.exe /singleplayer _MODULES_*Native*SandBoxCore*CustomBattle*Sandbox*StoryMode*_MODULES_ /anticheat"
- This should launch the game without needing the launcher.
5) Switch to windowed or borderless.
6) Close the game and reopen the normal way through Steam.