Shouldn't the past be the past?

Can i talk about something on my mind for a second? This has been weighing me down all weekend..I'm about to get personal.

How many of us can really say we leave the past where it is supposed to be? This is rather hard to do. I don't care who you are, there are some events that happen in the past that still affect your every day. It is impossible not to be affected by the things that happen in the past. The past determines the future. If yesterday didn't happen, there would be no today. If you lose a loved one like an immediate family member, it changes the way your view life (and death) forever. That is something you can't help. If your parents punished you for lying or stealing, it will change the way you view lying or stealing. You get my drift.
I live by the theory that things that happen yesterday should remain yesterday, not forgetting that things that happen yesterday can and will have an effect on what will happen now and tomorrow. I was recently reminded of an incident/person/situation in my life which, although now in the past, still has an effect on me. It's like a ghost that won't go away. Continuously haunting me whenever i think i have finally gotten rid of it. The feeling this ghost gives me makes me sick to my stomach...literally. I feel like throwing up. It is REALLY annoying to realize that one person can have a disgusting effect on you just by hearing their name. I don't want to go into specifics without writing a book here but basically, this person played me for a fool. Funny thing is, before i met this person, i thought i was invincible and nothing could pull me down. I had heard the stories of women who get played and considered them stupid for allowing themselves get carried away. Yes, i'm talking about a man if you didn't already know.
Well, i learned my lesson...i am, in fact, not invincible. I am not immune to everything like i once thought and i'm actually NOT perfect (sometimes). The point i am trying to make here is that when something happens which has a profound effect on you, it will shape the way you react to things in the future. Whether you like it or not. I was recently revisited by this ghost and usually, i deal with it the best way i know how; ignorance. This time, i faced the ghost head on. I did get the sick feeling in my stomach but i was able to defeat this thing which has been haunting me for so long. I spoke to a good friend who shed a different light on things and made me realize how utterly disgusting, despicable, useless, this individual is. Sometimes i wonder how they go to sleep at night. I have always striven to see the good in people but some people just don't have any good in them. That is another thing i have learned. Don't get me wrong, i am not bashing or resentful or angry at all at the situation or person although it might seem that way. I have acknowledged the past as the past and left it alone. On the contrary, I am angry at myself for allowing this ghost to haunt me repeatedly. For allowing one person to be like a poison, rotting my insides at the bare mention of a name. I take full responsibility for some of the things i experienced in the past because i should have known better but i try not to live with regrets because after all, things happen for a reason. I am angry at me, but that's ok because i forgive myself a lot lol Does it have an effect to this day? yes. But that is something i really can't help. That's how it is and that is life. I can't say i leave everything in the past because certain things just don't go away.
I feel like i finally defeated this ghost. It took me a while but better late than never. Things like that teach you that you are not immune to everything and most importantly, how to be honest with yourself. They say experience is the best teacher and although i would rather skip some lessons, i am thankful for every good and bad experience which leaves a lasting impression on me.

peace&love