Relationships and Trust

This question is about relationships and trust. I have been experiencing difficulty with a relationship between a guy and myself over the past six months or so. We are just friends, but the relationship has the potential to move to a more romantic connection based on a strong friendship. We care about and love each other deeply.

The problem is that I have had difficulty opening up to him as we have grown closer and, essentially have pushed him away. My fear is that this is permanent. I vowed to work on my issues, taking time away from the relationship, and told him that things would be easier for the both of us afterward. He will not speak to me anymore. I suspect that he is so sensitive, that anything I do just makes things worse. I feel like I am in quicksand and not able to make things better.

I know that men are actually more sensitive than women when they are completely vulnerable. Do you have any suggestions for how I can slowly build trust back with him and gently convince him to become open to the relationship being on the road to improvement? What are some things I can do show him that I am willing to open up?