Ex boyfriend and someone i currently like arguing?!?

I've recently started liking this person that i'll call 'bob' and im pretty sure he likes me back. I see him about 2/3 times a week and we're really good friends. However recently me and my ex boyfriend who we'll call 'fred'(which i went out with in year 7) have started talking again and my ex is being a bit of a idiot to me so i told 'bob' who has added 'fred' as a friend on facebook and is going to speak to him about it. Only problem is 'fred' knows i like 'bob' and im worried he's going to tell him, please help me?!