I've named changed for this. Writing here as I need to take the emotion out if the situation.
Car A waiting at a junction to turn right, protruding over the give way lines.
Car B driving on main road, slows to see car A at the junction. Recognises that if car A had no where to go if they were to let them out due to traffic on the other side of the road so continues on driving around car A. Car A proceeds to turn right and hits the side of car B.
I'm not too sure I've explained it clearly but can clarify if you need it.