Barbie...I agree with the fact that you don't need that in your life. Whether things change, who knows, but as is- no thanks.
No need to burn bridges, but time to move forward with your life and let them play in the mud.
One favor- read through 4mykid's threads (the first two). It will take you 30 minutes...but there are some conversations she's had that seem VERY similar to yours, and I think she's on a path you could benefit from. Tell me what you take away from it if you can make time to read them: