I know that problem. Especially with paper stuff, a postcard I had on my desk 20 years ago, some favorite clothes. I allow myself to keep some of these things.

If I start to clean up- like going through my clothes I can come into a real frenzy of throwing away or donating. The first pieces you still think and ponder - but then........

In clothes I usually give it away if I have not worn it the last season. Probability I will wear it next summer is very low then.