I had some really insightful thoughts about having closure in life, and thought I should write them down before I forget what I said:
I know there are plenty of people out there who don't believe in the whole concept of closure, like it's some hippie concept of alternative thinking or whatever. I, on the other hand, find that I need closure, I think it's an imperative part of growing as a person.
If I don't have closure with a particular person or situation, I am undoubtedly going to have a difficult time moving past it and forward in my life. For me, gaining that closure is a mental obstacle that is conquered. Once I have closure, I can completely shut down the situation in my mind and move forward in my life. It/that person becomes a valuable part of my life and who I am today, but is no longer a weight in my mind or my heart.
Bad relationships are a great example of that. There are all these hurtful, damaging things that have happened in the past, and that's all I can remember about that time. I've found that making closure with that person or situation lets me let go of all the bad or hurtful things I may be harboring, and relish the time/person for the role they played in my life. It's much easier to look back on your life with no regrets and no animosity when you can put those things to rest.
Over the last several months I have had many opportunities to really gain some closure on some looming ghosts in my past, and I feel SO much better about starting the new year, and a new chapter in my life because of it!
(That explanation is nowhere near as eloquent as it was when I spit it out the first time in real converstaion, but I think you get the idea.)