I've had a very similar situation, where my own insecurities made my ex feel insecure and that's very unhealthy.
I tried it all, all that I could to make her feel secure and once she uttered the words fed up I tried even harder and guess who ended up on the back burner (rocket science not required as a major). Simply put you've made her insecure with the ex you've been following on twitter and then there are the other issues (Mr. Long Fingers), but alas I personally think you've also hit the last straw you brought out a wussy side of you and she just can't take you back for that.
It's hard for you to move on I agree, but you're gonna have to swallow the bitter pill and dance to the music.
When a woman holds things against you its done, you're done, because whatever you do she traces back in her mind, whenever you argue she traces back. All that this does is put you in a weaker frame because from thence on all that happens is argument or issue -- she asks herself "He follows his ex, he stole from me, got on one knee like a wussy boy and and and''
You're in a very vulnerable situation right now, freezing out is not going to save you this time around. That's my personal opinion speaking from experience. Ofcourse we all here to give positive advice to guide each other but we have to be honest with each other.
Even if you fix things on Monday its gonna be temporary I guarantee you. Expect to hear the words "I'm not sure how I feel anymore, or I feel something has changed things aren't what they used to be" BE PREPARED TO LOSE HER!
You are the keeper of your own castle we can't decide for you but try offer guidance from here the ball is your court.
Go back if you feel things can change it will only be a learning lesson and thats what we want

(whether we lose her or keep her) we gain a lesson.
NO NO NO NEVER DELIBERATELY TRY MAKE A WOMAN FEEL JEALOUS YOU WILL GET YOURSELF BURNT!!! It will be incongruent especially in the light of your recent escapades...So you want to make her even more insecure???
ALL THE BEST.