So my lhaso-apso/shih-tzu Bunz has had a major aggression problem for about a year now. We had him to an aggression trainer and we thought we had a good start at tackling the problem but it seems like he responds better to my fiance and whenever I'm trying to show the dominant position he gets in his aggressive mode and growls, snaps at me, tries to bite and lunges at me. He has bit my nephew at least 2 to 3 times(never broke the skin but has showed his teeth and bit him), we can't even let him arouind him anymore. We live in a large apartment complex and we're close with pretty much all of our neighbors and even the children in this building cant go around him because he does same thing around them. Hes also bit my dad and mom but still never broke the skin. But whenever I try to be dominant to the dog, my fiance comes in the room and starts saying "what'd you do to make him mad??" and its like wow, whos the owner in this situation, me or the dog???
I cant stand the way he babys Bunz and tries to act like I did something for him to react like that towards me. Our aggression trainer showed us a way to do a gentle take down to show our dominance but whenever I do it, my fiance gets mad and says that he doesnt deserve to be overpowered like that and he did nothing wrong. I don't know what to do about his aggression anymore and I don't know what to do with my fiance's (for lack of a better word) ignorance? I love Bunz but I am getting to the point that I dont even like him and I'm starting to wonder how I will ever be able to have children of my own if he constantly snaps at kids.