Why does the past always come up in the future?

Sometimes the past needs to stay in the past! The bad date when you took a bite of pizza and just got all the cheese that slapped you in the face ... there's no need to remember that is there? The embarrassing things you said to someone you were head over heals for that just didn't come out right .... for example, offering him a Blow Pop (you know the sucker with gum in the middle), but didn't exactly say it right!! Nope, don't need to remember it ... however it is funny to look back on! The first guy that broke your heart .... forget him! Stick him in the past and bury him, jerk!
But what I'm talking about is more like losing a very close friend that you grew up with in a car accident the week before her graduation. Losing someone that was in your "crowd" in high school (you knew him ... not well, but well enough) to suicide. I could go on, I've had my share of death in my 31 years ... more than really! I was so shocked at my Aunts funeral to find out it was the first funeral my sister had attended! She's 12 years older than me, and there I was 20 years old and had been to more than I care to count! (She missed my Grandparents due to her pregnancies.)
Losing someone is hard, no matter who they are .... a relative, a friend, a co-worker you barely know, even someone you don't know but a friend does can be hard. No matter how long you knew them, how well you knew them, or in some cases, IF you knew them .... death is hard to deal with! Everyone has there own way of dealing .... some healthy, some not. Then there's those who don't deal with it, and just move on .... shut themselves off to that emotion, to the world, friends if they need to, and move on. (Good example of an unhealthy way that will ALWAYS backfire ... ALWAYS!)

Recently a friend of mine lost her boyfriend. I was there for her as I would be for any of my friends that needed me. As hard as it was for me to listen to her, to give her advice, etc ... I was there, and stayed strong for her. But on the inside I was a wreck ... it was digging up the past, I was reliving parts of my past again, parts I didn't want to. But for her, I did it! And to be honest, I think it was helpful to me as well as her. As I told her that he was there with her, he knew she loved him, he could hear her talking to him .... I could remember doing all that myself. As I listened to her talk, cry, mourn .... I offered all I had. My advice, my thoughts on life, and my experience with death. All of which helped her, and me at the same time.
At a time when I needed healing in that part of my life, I got it .... but the weird thing is, I got it from myself. From listening to my own advice. Sounds stupid, but when I listened to what I was telling her, things I believed ... yet, wasn't putting into effect in my situation, I got a sense of peace. And thankfully, she's gotten peace as well!

So why can't the past stay there .... we move on healthy and happy?
No need to give me an answer ... I know, nor would I want the past to stay there. People live through the memories you carry of them. As long as you have those memories, you have them. Personally, I wouldn't want to EVER forget about a loved one I have lost, no matter how hard it is to think of sometimes. Death is painful for the living, painful for the one's who loved them, hard for them to move on ... but that's what we have to do, move on. We move on with our memories, with them forever in our hearts. I've been known to be sitting, and think of something my Aunt Mary said or did once and just bust out laughing. I think it's her way of letting me know, I'm still with you, and not to be sad. As hard as it is not to get depressed, over the death of a loved one, we have to remember that as long as we hold the memories of them close ... they will forever be with us.