My dad told me he's not my dad?

Right now I'm really upset with my dad. My mom died a year ago today in a car accident and now my life sucks. My parents divorced 2 years ago. They hated each other. They didn't fight around me anymore but they hated each other and I never knew why before a couple days ago. Its was my uncle's birthday. He's not my real uncle but him and dad are best friends so he was over here. They were drinking downstairs and I was watching T.V. in the kitchen. Uncle Kyle mentioned mom's name and my dad just started going off about her. He was calling her horrible names so I went up to my room. He then followed me up stairs into my room and sat on my bed. He was so drunk but he said: "Mel, your mom loved you very much but she was a dirty . She cheated on me a long time ago with a man that was married and had children and had you." Then he left. I cried all night long. I was so angry and sad. I didn't say anything at first but it was driving me crazy so I asked him about it yesterday. He tried to deny it, but he finally told me the truth that he's not my biological father. The real thing that's pissing me off is who my dad is. 8 months ago, my dad picked me up from school early and said we were going to visit some family friends. He was so weird that day but I decided not to ask questions. We drove out to the edge of town and met them. This "family friend" turned out to be my bio dad but I didn't know that. My dad had told me that he was a special friend of mom's. We stayed for like 3 days. It so so strange. I had never met the guy, but he was so overly affectionate with me and his wife was nice but she was acting as if I had the plague. They had 2 girls and 1 boy around me age and they were cool. We never talked about them after that. I feel so lied to and deceived. I trusted my parents and they hurt me. I'm so angry, I mean, I think I need counseling or something I'm so mad. I can't even look my dad in the eye anymore. Does anyone that's ever been in this situation have any advice for me on how to cope? I'm 14 btw.