Most Helpful Girl
Don't let Instagram ruin your relationship.
I get she's in the wrong, but were the text messages you saw before flirty? Saying anything they shouldn't be?
I'd calmly discuss how you're feeling with her before you make any decision. You don't just make a rush decision on a 3 year relationship.
Most Helpful Guy
honestly can't stand dishonesty and going behind people's back. once that trust is violated it's over in my eyes and that trust is NEVER earned back. it's always in the back of my mind. because of this, now that I'm older, I end relationships pretty much immediately when a girl doesn't come clean when confronted.