Itunes reverts to previous libraries

so i need help, i drastically want to keep itunes becuz when done correctly it is by far is the simplest music program ive dealt with now heres my problem starting roughly a year ago: i was having issues purchasing music authorizing my pc logging in but those problems r resolved but this stuck around and got worse when i close the program it reverts back to a previous library date i dont know why, it was so where i would get day or so b4 it would delete my most recent changes then i have to fix it so i would set and forget until it came time to add new music, but now it happening everytime i close my Itunes program i add songs close/open songs are gone, i change song info close/open and reverted im losing my mind i dont understand why this is happeing plz help me....

Also ive backed up my music, completely wiped Itunes from my pc, deleted everything Itunes related in my User/Music folders reinstalled and readded my library which worked!!!!! now everything i do after: a new song gone... change a song title gone.... Im So Frustrated plz help me