Bf issues

So it all was good for awhile. We both came from bad relationships and one child from both relationships. The first 9 months were great. Then his dog bit my son in the face. It required treatment from a plastic surgeon for the sutures. At the time he was going to find a new home without kids for his dog. He pretty much lived with me at this time and we were making plans to get his place sold so he could officially move in. Well another 7 months down the road we live seperate he can only come over the days I dont have my son. I wont allow his dog around my son. He isnt giving me any hope on getting rid of the dog. He has even said well your son will be old enough eventually to be around him. I said never. I'm pretty sure I'm wasting my time but my son loves him and his son and he is a great guy other than this. I just need an outside opinion

My son is 8 and was 8 at the time. His dog is a pit and is 2. I reported to the dr all the Info the state just had him neture him. He was fine around my son the months prior. All he did was pet him and he turned and bit. The dog also bit my bfs sister in the face a few days after that. She was dog sitting so he could go to a wedding with me. The dog is fine with me and his son. He is actually very protective over us. I've been patient since july waiting for him to make the right choice so we can mive forward, but I don't see that happening. I don't want to be that person that says its me or the dog but I'm about to that point. I just have a feeling that I won't like the choice. Everything thing else is great other than this. He doesn't cheat, go out, drink or smoke. My ex husband was all of the above and I gave too many chances and wasted too many years.