I have a crush on my friend's dad. How can I get past it?

My friend Hayley and I have been friends since 1st grade. Our dads and moms are good friends and we all go on vacations, events and dinner at each others house. They feel just like family. Hayley's dad is always nice to us and sometime spoils us. He's a really nice man. When I was about 14, I started to get a crush on Hayley's dad, but I obviously didn't tell anyone. I thought It would go away over time, but it hasn't I'm 17 and I still have a crush on Hayley's dad. Every time I see Hayley I think of her dad and almost completely forget about Hayley. When they come over I always think about him first then Hayley. I told my mom and she said It'll go away, but it hasn't. Hayley's dad doesn't notice it, but when I'm around him I get really nervous that I may say something weird and he'll notice it. I think at one point his wife noticed, but the next day I think she forgot about it.I really don't want this to ruin my relationship with Hayley or our families. How can I stop it? and I already tried to forget about and get a boyfriend, but It didn't work.