Dreaming of the old

I keep dreaming about this person I know from my past. 

Like a thief in the night, when I least expect it, there that person is.

I can't for the life of me understand why. I read somewhere (or maybe someone told me) that if you dream of someone, that means you're thinking of that person. But I am not thinking of that person (but after the dream, that's a different story ofcourse). 

Someone told me (or maybe I read it) that the person might be dying or is dead and trying to tell me something. As far as I know, that person is very much alive and healthy.

I read (now this time I'm sure, because I googled it), that the person represents my anxiety or something that I need that I don't have currently. For example, if you dreamt of a highschool classmate that you have no attachment whatsoever but all you know is that person is the most shy person you have ever known, then dreaming of that person might mean, I am shy about something and I need to do something about it. Something like that. But I don't know what that person I dreamt represents. That person is doing OK in life, I'm doing OK in life. That person is smart, I'm not bad myself (how else did I ever got here and survived if I'm mediocre, modesty aside). I'm happy and content (pwera usog), that person is happy and content (I hope, I don't know much about that person anymore). What could it be then? 

I really don't know.

And it bothers me that because I dreamt of this person, I start to think about that person. I don't have issues about thinking of that person, mind you. He/she is a good person. I was fond of that person but I want to remember the good times and not the bad, and when I start thinking of that person I remember everything. The good, the bad, the ugly, the in-betweens, the overs, the unders, the left, the right. 

Everything.

I don't want to remember everything. Just the good ones.  

Just the good ones.

Please. I don't want to dream of that person again.