Thanks to everyone who provided advice. Lincoln's is doing better on his sleeping. He fell asleep within 10 minutes again last night. We were up for about a hour last night. I think a dirty diaper woke him up. That is still better than 2 or 3 hours! This afternoon he fell asleep in 5 minutes when I put him down for his nap. It seems that we are headed in the right direction.

I will say that this has been really hard on me. It's hard because I am the one at fault, and Lincoln is having to pay for it. I was really beating myself up about it until I got an e-mail from a friend. She told me that this doesn't make me a bad mom. Then she began to describe what is going on with one of her kids, and how she feels like a terrible mom right now. I happen to know that she is a great mom. After looking at her situation and my own, I really think that satan has been busy planting seeds of doubt in our minds. Lately I've caught myself thinking things like:
-If I can't teach Lincoln to sleep, how am I going to teach him to _____.
-All the other kids sleep through the night, what am I doing wrong?
-Consistency is so important. If I've failed to be consistent in this simple thing, how am I going to be consistent later on?

It doesn't take long before I really start doubting myself as a parent. When I step back and look at my parenting as a whole, I see that it is silly to think I'm a bad mom just because my child isn't sleeping. I'm sure this is just one of many hurdles that I will face. Though it hasn't been fun, it has humbled me. It has made me realize that I can't face this on my own.