exactly, I agree with above. You need to place your child's welfare above all else. If this means walking away then that will have to be the necessary choice.

Incidentally, I see that you have suffered a great loss in your past. I'm sorry to see that. I find it difficult to bring up but the question must be asked. Is it possible that you fear another great loss? This one you are in control of whether or not that happens. It is possible this is why you want to hang on.