I understand the fear of doing breakfalls. It took me at least two years to really feel confident with my rolls. My sensei told me a breakfall is a roll in mid-air so I should just keep focusing on my rolls and the breakfall will come. I have and the breakfalls have been coming. I found it's been best to push myself gradually, and visualize myself actually doing them with the confidence I have been doing my rolls.
Just keep practicing. I could give you all the advice in the world, but I know exactly what you mean that no matter how much people say there is nothing like actually doing the practice.
Over the past year and half (I'm 3rd kyu with 4 years of training), I have really been focusing on learning breakfalls. I started with the ones I felt more comfortable with and only did them with the people I trusted. I can tell you more, but go here: My Ukemi Journey
I hope it will provide you support and encouragement.