You have at least 3 corrupted savegames:
1CHARACTERSLOT_BETA_1
1CHARACTERSLOT_BETA_2
1CHARACTERSLOT_BETA_19
All three of these files are causing lots of logged errors and this will prevent you from creating new characters and saving progress on others.
You need to remove these files (including the temp versions) from the Saves folder while the game is not running.
Unless you have older backups that you made manually before the corruption, there is no way to fix the saves and the characters and their progress/gear would be lost.
Note: if you are using Steam cloud saves, you need to disable it before removing the corrupted files or Steam will just keep trying to resync the bad files. When enabling it again, you need to tell Steam to use your local files as the latest, not the cloud files. If you dont do this, steam will keep copying its copies of the corrupted files back to your local system.
Other observation, your 960 gpu is struggling with the game. Be sure to use lower settings to improve stability and performance. If the game is crashing, it can corrupt your savegames.
Make sure you are running the latest Gpu drivers and Os patches for your system.