The new guy is your rebound guy. And the rebound guy is probably
what you need to get over your ex.
However, rebound guy may also turn out to be the long term
guy.
Or , a rebound guy may just be your rebound guy.. but it ain't
gonna hurt you to give it a shot.
Depending on how the chemistry work out for the both of you.
If you don't try , you'd never know.
Reminiscence about your ex or ex-s is a very normal thing.
Memories are memories, unless you have brain trauma, they will
always remain a part of your life experiences.
You may fantasise or dream about them many years later, that's
absolutely normal.