I think Dee is on the right track, communication is the key here.
It was hard for me to learn how to communicate when I have never done it before. I was always one to keep my emotions hidden. Other than anger I never expressed emotions due to fear.
Happiness was also a hard one for me and even though my life is going great, I still struggle with it. I feel like a robot when I express verbally how happy I am. I think I sound fake to myself even though the feelings of happiness are real and I know it is important that I express them. It gets easier as time goes by.
If the other person knows you have a difficult time then they can be a little more understanding and reach out more themselves to get that affection and happiness started. Sometimes that is all it takes.
A hug, a smile and a kiss can go a long way.