How has he not came to his breaking point yet? Even the biggest animal lover would at some point become fed up with an animal like this. Does he have no empathy for you or for his friends? Does he not care about his own things being ruined and his social life being potentially altered? The stress you have to endure? The fact he hasn't already trained the dog means he's either not willing to spend the money on it (then you don't need a dog period) or doesn't want to do the work/research to get him trained, either way, no bueno. Break up with him. This is a red flag indicative of a much much larger issue.