hi - new

so i have been doing this since i was a baby, it started with just repetitive movement of rocking while sitting on the couch.  then i figured out i can add music and then my mind takes off somewhere else.  i dont actually create new characters and scenarios, but what i do is replay events or imagine events in my own life.  i think i am working out possible outcomes.  i do this for hours, every day after work,  just rocking with my eyes closed, listening to music, lost in my mind. i cannot remember a time in my life when i didnt do this.  if i am alone, i am usually doing this.  i have always felt really ashamed of it and hide it from everyone.  it has definitely affected my social life, and i am really introverted, although i am happy and i feel like i could make friends if i felt like i needed to. 

i am about to move in with my boyfriend in a few months and he is so cool he said i can have my own room because he knows i need a lot of space, but he doesnt know why.  i dont know if i should tell him or whether he will find it too strange.  he is pretty understanding.  For those with partners, do you hide it from them?  If/when you told them, how did they take it?  What if my boyfriend catches me doing it?  Should I tell him?