Is any of my behavior normal, and if not, what kind of help do i get, if any?

Every day of my life for the last 10 years, I have had conversations with myself. Actually talking to myself as if the people I want to talk to are really there in front of me. This bothers me because I really want to stop. This kind of thing has ruined my life in ways I cannot imagine. For instance, one day I was getting ready for a job interview and I stop right in my tracks of taking a shower and begin thinking about this guy I dated who made me late for a previous interview by asking me to take him to work. The conversation and thoughts in my head begin pouring out. My mom heard me talking to myself. She asked me was someone else in the room. I responded that I was on my cell phone. That was not the truth. There was no one there and I finally realized that I was already late for the interview. When I got to the interview someone else already had the job. Another incident was I was in a car accident actually thinking about something in my past when I hit someone from behind and was given a 10000 lawsuit. Several of these incidences have taken place for years in my mind and I actually play them out as if the people I want to confront or the conversations I want to have with certain people confronting them about something in the past that I could not control actually take place in my mind and in oral conversation by myself. I do not know where this comes from but can someone please help me?