Here is the reality: If it is something you haven't used in the past, it is likely you won't need it in the future. What is the very worst thing that can happen if you give it away or ditch it? Weigh that against the fact that in that place you get more space for things you need, love and are keeping. A gift? It's doing no one any good in the back of your closet taking up space. Maybe someone else can use it, and wouldn't that make you feel good, in addition to getting some extra space back!
How about the excuse "But it was free." Free is my favorite word, but a long time ago when I was in my 20s waiting in line at the drug store to get my free Polident Denture Cleaner (for which I had ZERO need) I realized I had gone a bit too far. Now I get only free things that I can use, or donate to someone that can! If you have some free stuff you aren't using get it out of the house NOW.
"But it was expensive!" If you don't absolutely love it or use it then it really doesn't matter WHAT it cost, right? But, I'll give you this... how about a consignment store, Craigslist or Ebay? If it is worth that hassle, great. If not, donate it. Be realistic. We always overestimate what someone else is going to pay. And, if you donate it there is that wonderful receipt for your tax returns next April.
If it has too many memories, try taking a photo and keeping theses digital pictures in a folder when you can keep those memories, but not the clutter.
Give it a try. The calm you create with less clutter is so freeing!