The EU is not negotiating in good faith? Oh, we knew you'd find a way to blame the EU for basically anything, but this is quite inventive. The UK has no red lines. That's the only constant in these negotiations about the UK position: It has none. Now that they finally got almost no confidenced, May and her team has put together a program that's basically trampling all over what the EU has said were its red lines even before negotiations began: The core principles of the EU.
And you say the EU is negotiating in bad faith? Why, because you once heard someone utter bad faith and thought that it sounded impressive? I don't think you even know what bad faith means. Ireland is not a Pinata, it's part of the EU. As such, Ireland's interests are the interests of the EU. Just like the EU core principles are of the utmost interest to Ireland. Break down the four freedoms and the EU is meaningless. Not just for Ireland, for everyone. But yes, also for Ireland.
The only ones talking in bad faith are you and Dribs, really.