Because life is like that, isn't it? If you thought of all the tiny things that divert your path one way or another, some good, some bad, you'd never do anything ever again. And some people don't. Some people go through life not really deciding to do much, not wanting to, always too fearful of the consequences to try something new. Of course, that in itself is also a decision.
You see, for me, memories are difficult. Very often, they hurt. A curious thing about grief is the way it takes your entire life, all those foundational years that made you who you are, and makes them so painful to look back upon because of the absence there, that suddenly they're inaccessible.
Low self-esteem is the belief that we are not good or worthy enough. It's a self-perception. You can be wealthy, beautiful, or well-liked by others and still don't feel good about yourself. The way other people perceive you doesn't affect your self-esteem. It's how you perceive yourself that matters.
Maybe if you thought about them, people never really disappeared. It sounded so corny, but there was a scientific explanation for it, too. If you believed that thoughts were energy and energy is matter and matter never disappears, then a person can never truly leave you unless you stop thinking about them. Everything you shared with a person is still there swirling around in the universe.