Long lost father

I don't really know what to think about the whole situation. I'm so confused that I don't even know right from left anymore. All I know is when I saw him come into that restaurant my stomach felt like fire and my eyes were tearing up I just knew it. The fake yawning thing doesn't get me too far, especially because it's not like they stop after that. I feel like I should be ashamed for being out with my mom and her knew boyfriend after my mom and her fiance,(not my father) split up. He says he would like to stay in the picture as my dad but the further him and my mom drift apart the less he talks to me. I thought that this was a joke when he first told me too; but I gave it a shot. Just to see how much I could really get out of the whole situation. Then after a few times of us hanging out as "father and daughter" I wanted it to happen more and more because you see my real father died right before I turned four so I lacked in relationships like this. Then he started catching on to the fact that mom was seeing someone else and he would text less, call less, he doesn't even say I love you anymore. I almost feel like I have lost another father over again which was the first thing I didn't want to experience. I don't really know where I stand as far as having a dad anymore. Maybe it's best to go without, but without is getting pretty damn lonely.