Thank you for all of the suggestions and input! I am definitely learning alot from everyone!
I believe the alternator is the problem here. I went to AutoZone last night and had them run a load test on the battery and the alternator. The battery test went fine, but the alternator test showed otherwise. I put it in drive and then in reverse while he tested it and as I had mentioned before this is where the car would just shut off when it was around freezing and/ or the lights would dim and then brighten back up. The output when I put it in drive was 66 amps and the output when I put it in reverse was 43 amps. The standard output (according to the service manual and AutoZone) of the alternator should be 120 amps across the board. So I definitely think this is the issue. I'm guessing that the output of the alternator was just enough to keep the battery at a decent level and then when it was really cold and I tried to start it, the alternator couldn't handle it.
I went ahead and posted a video of what the dimming looked like when I put it in drive and reverse:
YouTube - Crossfire Voltage Problems
I did also go ahead and purchase a new battery as well as the one I had was the original. I opted for the Optima 34R battery that was at AutoZone. I price-matched Advance Auto next door because they had it roughly $30 cheaper. In order to bridge the gap between the height difference, I bought a rubber exhaust insulator and put it under the bar that goes across the battery. It worked quite well and the battery fits in there fine.
So my next step here is to replace the alternator. I looked in the service manual and it doesn't look like it would be too bad to do but the only thing that i'm concerned with is working with the belts. I would appreciate suggestions on where to get a decent alternator as well as if someone has replaced it in our car before and how difficult it might be. I have never replaced an alternator before. I am also going to use the search here on the forum to find some more information.
Again, I appreciate everyone's input. Oh, and I did go ahead and put some STP complete fuel system cleaner in the fuel tank as well for good measure
