No, no, no, you are not the only one. I guarantee it. I don't know how reassuring that is to you, to know you're not the only one. Specifically the anxiety, for a lot of us. The insomnia and anxiety make a nice little feedback loop, each feeding the other.
How old are you, may I ask? Exhaustion and sleep deprivation aren't exactly the same, but both can be crazy-making and disheartening. They just take wind right out of your sails. Sleep deprivation was my particular problem and I think it probably took years off my life.
Are you getting medical attention for your insomnia?
Thanks for your kind thoughts. For sure the anxiety is feeding into the sleep problem. I don't want to hijack this thread though (which is very interesting!) - my insomnia thread is here, and you can see what I have and haven't done about it (mostly haven't, to my shame). http://www.mothering.com/community/t/1380656/chronic-post-partum-insomnia
I'll be turning 43 at the end of the year. Was 39 going 40 when I had my daughter.