Welcome to the place of relief where clutter filled house owners come.
Pack-rat, collector, lover of all things, it just comes down to one basic term for all of that stuff - clutter.
Whether we like to think about it or not, stuff can accumulate pretty quickly, and then what do we do? For some of us we become "clueless in clutter."
Start with the basics. The closet. We love all of those clothes we have, and some of them are from an "era" that holds many memories for us, but honestly, closet space is valuable. Weed through those lovely outfits and find the ones that you have worn to death (i.e., holes, stains, in utter disrepair, and no hope of even being saved by a needle and thread). If they are that memorable, put them on and take a picture of yourself wearing it. That way you can then properly dispose of it, but remember the feelings you felt while wearing it while viewing the photo.
Fits, doesn't fit, never fit. Many categories of clothing find their way into our closet. We all have the dream of losing that last 10 pounds, but honestly, it has been 10 years and that 10 pounds is still hanging around. Pull the clothes that have been hanging for over a year with no wear. You may even be able to find them by the build up of dust on the shoulders, or the permanent hangar marks embedded in the clothing. Something too big? Get rid of it! Who wants a reminder of what they were? Not me! I don't want to be that size again - good bye over-sized clothes!
Anything leftover in the discard pile that is of a good "cleaning" consistency, such as t-shirts, cut them in nice pieces for quick cleaning. I love having a mess that I don't want to ruin a "good" rag on, so I just pull one of these out and then throw them away without worrying about cleaning them. Old jeans? Cut some nice size squares to use for patching kids jeans.
The rest of your collection that has found its way to moving on can be joyfully donated to your local Goodwill, etc., and you will get a nice receipt for a tax deduction!