My Dad wants to get rid of my dog?

My dad is crazy. Nothings ever good enough for him. He can always find somthing wrong with us. Since I was 6, he would swear to me saying about how we dont do anyrhing around the house or pick up after our selves. We do, he only takes care of him self. My mom refuses to get a divorce becasuse it would be too hard on me and my brother. But he always tells us he is gonna leve one day and never come back. I used to cry about for days. But now i just think its nothing that i did and theres nothing i can do to change it. I have a little dog, and we have a little fenced in section in our back yard for it to go. I clean it up. But, if i forget one week, he goes crazy and says hes gonna get rid of the dog. I know hes seroius. And just today, he reminded me again. But he was yelling and screanming and.. u get it. He seroius tho. Hes already piked out a shelter where hel leave the dog. Im scared to leave the house for sports and stuff, cause i dont know what hes gonna do. Im only 12. What Should i do? And please dont say go to an adult of whatever cause my mom nos but she works too and she cant do aything about it. Thanks guys!:)