The fact that you feel like wanting to be with him shows that you like him and he certainly likes you too. A man with sadistic tendencies might be the right one for you; you have to know for yourself what you like and to what extent.

But I am sorry to say that I see a severe problem in your communication: If you are worried about the bruises, expressing your thoughts and he is ignoring that, even denying reality, then there seems to be a severe problem for me.

But what advice can I give?
If you feel like wanting to give your love and devotion to him, that is what you shall do. I do however recommend to think about all that. If you can't get through to him, reach this point of opnenness it means a lot. I do however not know the situation: How have you tried to talk to him? Might the situation be misunderstood by him? Did he think that you were teasing?
Maybe, you should try to talk to him about that serisously in a quite minute apt for this.
If that doesn't work I would think about the whole situation!

It is not the sadistic drive that is of any problem, but a lack of control and the denial of it in the interaction with the partner

I am sorry for writing such a negative reply, but it's true