Wow, beario. It's wonderful that your child is all right now, but I'm sorry that you feel you lost a part of yourself. How long was your child ill? Any extended illness, especially a terminal (or thought to be terminal) one, will wear down family members of the sick person. Have you taken any time for yoursel, since your child got well? Assuming that she is healthy now, and that you have a husband or partner or someone to keep an eye on her (if she's old enough) or flat-out babysit her (if she's still young), you might want to consider some sort of spa vacation for yourself, or a spiritual retreat (whatever faith you are, if any). I know that some monasteries offer rooms for rent cheap, and you don't have to be Catholic or Christian, you can just
be there, and rest.
Alternatively, or maybe in addition, you might want to consider some therapy. I hope you don't take offense at that -- I by no means mean it in any sort of bad way, I just think that it might help you work through your feeling of being incomplete, and maybe get you back to feeling like yourself, whole.
Also -- did you give up some creative or artistic pursuit when your child got ill? For example, did you used to paint, and gave it up to take care of her? If so, now that she's well again, you could take it up again. Maybe that's what's missing.
I hope at least some of this has been helpful, and that you're feeling back to yourself soon.