Living in the past is one of my biggest , if not the biggest ,
problem I face on a daily basis. It mentally paralyzes me.
Like drowning in quicksand. So these thoughts just come into
my head , uninvited. It makes me think about things I don't want
to think about. So I found that by practicing mindfulness meditation
you can recapture your brain and thoughts. I keep it very simple.
I just concentrate on what's in front of me at the moment.
I also just concentrate on my breathing. Something that most don't
even think about. I need to be in the HERE AND NOW ! If I do that
then there's no room for the past. My mind is filled with the now .
I would look into mindfulness. It helped me , I hope it can help you.