I had to let my sponsor go because i felt he was holding me back on the steps. It was a heart wrenching decision because he had helped me out such alot. Looking back however i feel as though he had become more of a therapist than a sponsor. A sponsor should be someone to help you through the steps, if you've tried to address the situation with him and it still doesn't happen then your sobriety (which means working the steps) is what is most important. If you feel you can work the steps better with another sponsor then have the courage to confront the issue with him.
After i let go of my old sponsor we had a really nice chat about how we still want to keep in touch. He helped me through so much, he is the one that can identify with ex wife and children stuff, whereas others (including my new sponsor) can't. We are now good friends, i still turn to him for advice but he's not my sponsor. I had some issues last week with my daughter and guess who the first person i phoned was...my old sponsor.
When i spoke to him about i felt i wanted a fresh start with someone new, his first response was that it was my sobriety and i get to choose how i work the steps. We now have a marvelous relationship and i'm glad i chose another sponsor.
Do what works for you, if you feel you need another sponsor there is nothing wrong with that.
Paul