I didn't really like Courtney before the "Jack or Marcus" thing... I think it started back during the M/J/C triangle business. I grew to admire her individuality though, which got lost a bit after she hooked up with Joe College. Courtney was always a character that needed more development, so I could hardly relate to her. So like Shelly, I was bored with her.
I'm still hooked on the Jack/Dex possibility. I just feel like something had to have happened between them.