2003 GMC envoy xl wont start

Hello, I have a 2003 GMC envoy xl, v8 that wont start. We
turn the key to try and start ut and it gets full power to
everything, the lights radio, windows, etc. The issue it it
doesnt even make a noise like its attempting to crank over.
Weve spent a lot of money replacing parts to try and fix the
issue but nothing has worked so far. We have replaced the
starter twice, the ignition switch, the fuel pump, and a
bunch of fuses and were still in the same situation. What
else could be causing this? Weve looked at all these
forums for days and weve attempted 99% of everyone's
suggestions but I'm hoping to find a few more before I have
to throw in the towel.