Looeez,
When i started biking over three years ago there were some long daunting hills like you describe that made me feel like I was going to have a heart attack, my legs were screaming in pain, I was gasping for breath and making the most awful gasping noises.

Now, just by having ridden them repeatedly, they present no special problem other than my breathing a bit more deeply and my heart rate rising a bit. No gasping, no pounding heart, no leg pain.
I don't 'train' or ride huge amounts like some others, I just do various 10-30 mile routes maybe two or three times a week. The routes are a combo of hilly and flattish, with a few pretty steep hills thrown in.

It WILL get better, don't sweat over charts and graphs, just ride and it'll happen.