Dad left me for a new family?

I’m tired of my dad letting me down. I’m 16. I don’t live with my dad. I lived with him for the summer and like they have no standards. I was the cleanest out of all of them they didn’t take care of themselves and didn’t keep their rooms clean. that included my dad it was ridiculous how dirty they were. I’m lazy but I have standards. The only reason I go see him now is because of my dog and I’m trying to save money to get him neutered.I live with my mom. My dad left me when I was younger for about a year iI know it was a long time. He said "he was getting his life together" Finally after all that time i see him again. He takes me to meet his new family. He has a new wife and a stepson(18) and stepdaugther(16). They bully me and i’ve told him about it and he just laughs. To me he shows more care for them than he does for me. His house is super dirty they have a dog that pisses on everything and there never clean it up. I don’t like spending nights there because of how dirty it is. I alays have to sleep on the couch because i have no room there or even at least a guest room. They are more active i would say than me because there in rotc/sports and have really high rank and i was in rotc and quit because i didn’t want to do it and then my dad wouldn’t talk to me for over a month. Now my dad is saying he;s gonna help me get a driver license and teach me to drive. It’s been nearly 8 months since he said that. So now my mom signed me up for driver’s ed and I asked my dad too help and he said he wpould give me $100-$200 to help out but then when it came time he didn’t. He said "Don’t play me" I didn’t play him because he said he was gonna help. he only took me driving twice but has taken my stepsister dozens of times. Christmas came by and he didn’t get me anything but they got ipods and everything. my birthday passed and he didn’t do anything for it. There birthday came and he went all out. Another christmas and birthday of mine go by and he does the same thing. I know I’m tired of this and when i try to talk to him about it he takes it like its a joke. he calls me names like nerd and stuff. I’ve tried multiple times. I’m to the point where I’m thinking of cutting him out of my life if he’s going to be that way. Everytime I need him he abandons me. What should i do and how would you feel if you were in this situation?

if i were u i would feel terrible, really terrible. i think that u need to send him a letter or something, really seriously, in it put how u dont like him mistreating u, make it really formal, and im sorry but personally i would cut him out of my life if i was you, he obviously isnt worth you or your time. if he gets really mean or harsh or violent to you threaten to take him to court. you have to rise above this, and focus on the really good things in life, and drop the parts that are weighing you down so you have space to spread your wings.
hope this helped xx