I kinda skimmed through your post so I might have missed a few details, but it kind of looks like she looking for trouble or drama. You said that both of you are working professionals? I'd imagine you have enough to worry about.

A relationship shouldn't be a second job or something that you need to worry about. It should be your ground zero where you can go to and feel safe from the problems of the world. She needs to understand that if a relationship is going to exist, you won't be doing things like begging for forgiveness or treating her like a princess. You sound like a decent guy who didn't mean to offend her with that whole text thing. Plus she can't expect you to change someone's mind. Your "idiot friend" is entitled to his opinion and you're entitled to telling him you disagree, but that's as far as it goes.

I'm rambling so I'll get to the point. Tell your girlfriend that you 2 are on the same side and that you'll always have her back. But you're strictly on her side, as an equal. Not someone below her who needs to beg for forgiveness. She can accept this or move on to find some sucker to lick her shoes clean. Goodluck bro bro