Pemberley, please get *yourself* to an amazing doctor who will give you a full physical, and also go see a counsellor about feeling depressed! It sounds like you're completely burnt out, and you're crashing. I know it's easy for someone on the outside to sat "take some time off!, even though it's perfectly clear that No One can do your job. Right now, your daughter in a good place, she will need you to go to bat for her again soon. Until then, it's okay to let go a little. Heck, it's okay to grieve a little, crash a little, let emotions come you simply didn't have the time or energy for.
Remember your daughter is exactly who she is. Her talents compromised by struggles. Her struggles compensated by her talents. She is a unique package and asking "what if" isn't fair to you or her.
I keep fighting the "what if" myself. What if my oldest weren't held back by his anxieties and depression. What if my youngest could walk and talk, didn't need walker, wheelchair and all those therapies, how will his body ever be able to do right by this amazing little mind trapped inside (he can play Uno and appears to be an emerging reader at three). What if we had the time and money to let our daughter develop her talents, not be overshadowed always by her brothers whose needs tend to be so much more in-your-face? Don't go there, I tell myself. They are what they are, I'll just work my butt off to help them be happy and useful.
And it just occurred to me I've forgotten to go to my exercise class yesterday *again*.