Oh my, I've been here myself. My head was filled with mixed feelings and doubts. It turned out I was holding onto the past and not facing up to what my future really should be moving towards.
It was subtle and we both just fell into a perceived routine. The guy I was with at the time was being supported by two ladies so he was happy. I thought my life was being fulfilled but it was a false sense of security. I was just going around in circles.
You need to remove yourself from this situation and find someone who can be yours and yours alone.