Parenting Crisis!!?

My mom and step dad got a divorce over the summer!! He was the only dad I've ever had!! Now a don't get to see him except maybe once a month!! I miss him so much!! My moms new boyfriend gets mad anytime I even bring him up!! I don't like her new boyfriend at all!! He tries to be my dad, but I don't want him to be!! I'm 18 years old and he still tries to tell me what i can and can't do!! ANd on top of that my biological father is in jail for seven years!! Although I haven't been around him my whole life it still upsets me!! He's not going to be there when i get married, when i have my first child or anything!! It really upsets me!! Even if he hasn't been the father he's suppose to be I still love him and I don't want his grandkids to be born with out him knowin who they are and getting a chance to see them!!