I used to have the same problem. I just couldn't say those three words! I got very anxious and felt too vulnerable to say them, I think. Since 1 ½ year back in time I've forced myself to learn to say those words and now after a lot of "hard work", I can say them without almost fainting.
I've actually been helped by coming to this site and seen people show emotions by expressing feelings in words. Also by starting to write poetry, I've opened up much more.
Therapy- getting to know myself, has also helped me.

You'll get there, hon! Pm me anytime!