04 Civic wont crank after alternator replacement

[Haywire421]

My 2004 civic VP 1.7L w/ manual transmission had a bad alternator last week.  I had the alternator under warranty, so I picked it up and brought the new alternator and car to my mechanic who installed it for me.  After it was released to me, the car started up like a champ for about a week, and then, after bringing a friend to the store, it wouldnt crank at all.  Lights and radio were still working fine, so I didnt think it was a dead battery.  Popped the clutch and brought the car home, took out the starter, and then went to the auto parts store where the starter also tested good.  All of my relays and fuses tested good too.  I noticed that my mechanic didnt screw in the ground cable coming from the thermostat housing back into the front of the frame, so I screwed that back in hoping it was the issue; it wasnt.  After that, I noticed that coming out of the same conduit as the starter hook ups was what appears to be a wire w/ a pigtail connector that connects to either some kind of sensor or maybe a ground.  On the sensor end, all the plastic was broken off that the pigtail would lock on to, and I was able to remove the pigtail by simply just lifting it up off of the sensor w/ my pinky finger; didnt have to squeeze or anything.  We couldnt identify what the sensor was, but figured that it might have come loose while driving, so I gorilla taped it down so it couldnt rattle off; car still wouldnt crank.

Just to clarify, the starter doesnt seem to be getting any power.  It doesnt turn over at all.  The ignition relay makes a click when I turn the key and you can hear the fuel pump turn on too.

Any ideas?