Congrats on going Whole Grain J.!!
It really tastes great after you get used to it. For spaghetti it is all we use anymore. I had the same struggle with al dente vs mush. When I cook it, I would rather have al dente than mush, so when it hits that all important "box prep" time, I get out my colander, walk around the house once, check laundry, etc then come back and get them out. Just kidding. I don't take that long, but it sure seems like it. Hover over that pot until you get that perfect texture/softness. It is hard to achieve, but can be done. There is no exact time from what I've discovered.
I do hope some of that helps. My family has gotten used to the slightly chewier version of pasta because it tastes so good!! OH, and we don't buy spaghetti noodles for spaghetti, we use Thin Spaghetti instead. That is just what my picky husband likes best. Maybe try that. It might soften up faster!!
V.