M.L.
At his age, waking 3x a night isn't exactly what I would call normal. You do sound more like a human pacifier... that is exactly what my pediatrician told me when I was going throguh this, I felt like I was nursing a big baby for the vast majority of the day and night and was plain exhausted and drained.
Here is some helpful advice Dr. Sears suggest, especially for the nighttime issues:
http://www.askdrsears.com/html/7/t070800.asp
As for him not eating during the day, he has you trained! He knows you will nurse him soon so he isn't eating. Very smart little guy. Well, spread out the nursing. He'll fight and cry, but he'll get over it and used to the new routine in a week or so.
I nursed both my kids till they were about 16-18 months. Really, one was read to wean, the other wasn't, but I couldn't do it anymore (my sons was also a big biter), and then I just did night nursings. My husband would often have to pry him off of me and he screamed while wildly ripping at my shirt. My husband would take him, cuddle him and play with him, to try and take his mind off of it, because if I tried too, it didn't end without him battling to nurse again.