I know someone already suggested a way I can test the lift pump, but out of curiosity, where in the fuel delivery process does the lift pump come into play? The hand primer has a hose into it and a hose coming out of it, does the lift pump move fuel from one of these hoses to the other (the same way the primer pump does) or are they just located near one another?

Also, in response to Jooseppi Luna,

1) I may be paranoid, but I have seen water and diesel together before and it reminded me of this (a little). I actually saved the diesel form the filter, hoping someone would think this was relevant. I will post a picture tomorrow.
2) I have gotten diesel from different sources, and it could have been poor fuel, but either way, I still want to know why fuel isn't coming out of the IP.
3) As far as I can tell, there are no leaking gaskets.
4) The way I washed the tank, I think should have been okay, but truthfully I am a little paranoid about this....I removed all lines going to or from the tank. I sprayed in some engine degreaser. I used a power washer and sprayed inside the tank. I drained the tank (by removing the strainer on the bottom of the tank). I did this again. Then, I let the tank sit for several hours with the strainer out and the fuel cap off. Then, I filled the tank up with 3 gallons of diesel. Using my OTHER tank, I drove around my property, taking hard turns, stopping short, etc. to try to get the diesel to slosh around in the tank. I then drained and safely disposed of this 3 gallons of diesel (which looked very clean to me, but I didn't want to risk it. I then put diesel in the newly cleaned tank primed the lines for that tank and ran the engine off the newly cleaned tank. I drove it around my property on that tank for about 30 minutes and concluded that everything was a success. I even started it on that tank a few days later, and eventually unintentionally ran that tank dry. I hope I didn't make an error here and cause water contamination, but before this new issue started I switched to using the OTHER tank and used it for a week or so (on my property only) and there was no issue at that point.