I've been constantly thinking about someone from my past and people related to them for many years now. But I never miss any of them. My emotions when thinking about them range from anger, regret, and indifference. Pretty much all of my experiences with them were god awful, but they sure were memorable, if nothing else. I think the only ways I'll stop constantly thinking about them is if I get a really good, really busy job, I fall in love and start a family with someone else, or if my band really takes off and I get wrapped up in that. But since the time I interacted with them, my life has pretty much completely stalled so I got nothing to keep them off my mind.