Hello, I'm Jason. I will do my best to answer your question quickly and accurately using the information you have provided.
my first question is whether you've had the battery load tested yet?
these cars do have a tendency to go through batteries fairly quickly
let's start there before going through any other diagnostic steps.
all of the symptoms you're describing sound very much like a weak battery
if it drops under approximately 300-350 amps, the car won't start
please let me know if there is any further information I can provide