I'm highly intelligent, but emotionally and socially inept; can I still lead a happy life?

YES, you can still be happy. A rough childhood just plain sucks, there is no way to sugarcoat that. I'm not so sure that you are emotionally retarded- just the fact that you realize your emotional upheaval has taken a toll on your life tells me that you are capable of managing your emotions in a positive way. That doesn't mean it's easy- just that you are cognizant of the effect your childhood has had on you, and understanding that is a step in the right direction. Do you have a therapist you could talk to? Or a suppot group?