There are a number of programs that will weed through your music library and remove duplicates. I’ve never used any, so maybe some Team UfYH members will have some suggestions.
Beyond that, work in intelligent chunks. Set a timer, and work in 20/10s or 45/15s, taking your breaks so your eyes don’t cross from staring at file names. Start at the beginning. Work your way through, methodically and carefully. Take breaks. Give yourself plenty of time to do this. Don’t try to do it all at once.