S.J.
DEFINITELY get the book THE BABY WHISPERER. Also helpful: Healthy Sleep Habits, Healthy Child. The Baby Whisperer doesn't believe in letting them cry it out, and the Dr. who wrote Healthy Sleep Habits gives you either option in his book.
And they both cover every issue that you could possibly deal with from birth to age 5 in regards to sleeping and eating habits. These books are life savers. And...I know you are exhausted, been there, done that. But you must flip through at least one of them and find the sections that appeal to you and it will change your situation if you apply it. Both books have advice for nursing/cosleeping, etc.Hang in there! My second one is 5 months old and my firstborn is 3 and I'm tired, but I'm getting more sleep than you, sorry to say it. I'll say a prayer for you!