Changing main characters.

I've had intense daydreams since I can remember and as I've entered different phases in my real life I have changed my main characters. Usually I'll introduce the new main character into my daydreams by making them come into the old main character's life as a friend or a person they interact with and then at some point I'll just completely change over to the new main character and stop altogether with the old character. I can't even say what happened to the old main characters. Like I said earlier this occurs when I enter a new phase in my real life so I don't know if maybe it is a coping mechanism to deal with change and let go of past people and situations in my real life by creating a new character. I just wanted to know if anyone has experienced anything similar.