If you find yourself saying any of the following things, STOP and step back and think about what you are saying:
"We paid good money for that": People use this argument to "keep things" that they should get rid of. The amount of money you paid for an object is irrelevant - if it is something you no longer need or use and it is merely cluttering up your life.
"That's worth something, we should keep it": Again, the value of something is irrelevant to its worth to you personally. An object that you are not using is just clutter, and if it has value, then all the more reason to liquidate it.
"We planned, five years ago to....": Basing your life on plans you made 5, 10, or 20 years ago is silly nonsense. Yes, you made plans 5 years ago. But circumstances change. Change your plans to fit changed circumstances. Trying to live out a "plan" that is no longer relevant or makes sense is idiotic.
"It has sentimental value": While family photos (when was the last time you looked at these?) and other "keepsakes" may have sentimental value and are easily stored, things like furniture, cars, and other large objects (or large numbers of smaller objects) are not practical to keep for sentimental reasons. Living in the past and being all maudlin and weepy over past life experiences is never a useful way to spend your time - or good for your mental health. Cherish the past, and move on. Keepsakes and mementos are fine and all, but don't drown in a sea of them, or you will be unable to appreciate the present.
Stop and think about what you are doing. Living your life around material things is rarely a good idea. Obsessing about possessions and owning things is nothing more than a form of slavery. You can enslave your entire life to the acquisition and maintenance of material things and end up none the richer for the experience. In fact, you will be impoverished, both financially and spiritually.
If you want to live a free life, you have to free yourself from the material - the wanting and needing of things to make your life complete. Materialism is a false God, and one sure to make you miserable in the long run.
(Probably the only smart thing she ever said)