Its OK to:
Sometimes just being yourself. At peace and not bothered about being judged.
Go for a movie alone.
Be with yourself. Listen to your inner imaginations/thoughts.
Not pick up calls.
Wrap yourself in bed and stare at the ceiling.
Cook for yourselves, your favorite dish (This one for ladies)
Smile alone while reminiscing old days.
Laugh at the silliest joke in the books.
Go back in time with memoirs.