You are not alone in your thoughts. Your wife has disrespected you for many years.
That’s the black and white of your situation.
You don’t need to confront her work colleague. Your wife is the one that needs to change. Change her attitude in how she lets other men talk to her, interact with her and thus, stop allowing herself to be "used" for their "jokes" or innuendo.
I can share that my H was always a bit flirty with other women, even in front of me. It was always very harmless but I learned how other women were "interested" because he listened and joked around etc. It was never inappropriate but people genuinely like him.
However when he started cheating I realized MY mistake (same as you). It was no longer tolerated but of course I became "the crazy jealous wife" blah blah blah.
I don’t have a solution for you to get your wife to see your point of view. I got my H to see mine because during his last affair I kicked him out and told him I was D him. I had enough of the disrespect + lying + cheating.
It wasn’t idle talk. I meant every word.
Long story short he realized his mistakes and the disrespect he showed me. He made some significant changes and we are very happily reconciled.
In short order at the time if dday2 I did the hard 180, emotionally detached and started my own social life (he was not invited). I have my own $ and put myself first every day.
My H knows there are no more chances and I can (and will) walk out the door in a heartbeat. He also knows he caused me to become this person.
[This message edited by The1stWife at 11:42 PM, Friday, December 5th]